You know, this is something that's needed doing for quite a while. I wonder, once the design is 'completed' (are they ever REALLY complete), would you be interested in working out a deal to put your system into production? Maybe something along the lines of royalty / licensing payments going to a school club or science department, or something of that nature? Since it's your own complete design, and I'm assuming your own code, there wouldn't be any outside licencing issues to worry about.

I'm not sure what I would license. Most of the hardware is either open source(Arduino) or just basic circuits(MOSFET driver boards). Even the switch board is just a series of shift registers. I'm adding in some OPP hardware now. For the code, it's just Arduino code on the controller side and MPF Python on the other side. I couldn't copyright my changes to MPF even if I were inclined to do so.
And I didn't redesign the playfields(even my more in-depth Flash retheme is just getting a new magnet under the hood). If I ever build a completely custom playfield, I will revisit the question.

Ok, ripped the PCBs off and put in a couple of orders for parts. The new coil and switches are on their way.
Next Steps:
1) Mount switches directly on playfield
2) Replace burnt coil
3) Replace my hack power system with the OPP power filter board.

I had some switches lying around, so they are going on this week.

New coil installed. New spoon switch for the pop bumpers.
Currently printing a bracket to hold the switches.

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While I'm waiting on parts on the fireball, the cabinet rebuild for project #2 is proceeding. It's starting to look like a pinball cabinet again.

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You have a good eye. It was, indeed, a Gulfstream. However, it had some serious corrosion issues. I suspect that the backbox and the front of the cab were both exposed directly to the elements.
The guy I bought it from restores EMs, and he was selling it as a parts machine. I needed a cabinet for a project, so I picked it up. I don't think that he thought the cabinet was worth saving. Parts were delaminating, and the front was a loss. Surprisingly, the coin mech looks salvage, when the mechanisms behind it were ruined. So, I knocked the front off, started gluing laminates and making liberal use of wood filter. This weekend, I finally got around to making the cuts for the front. Had to eyeball most of the angles, but I think it came out ok. Probably would have been less effort to find a better cabinet, but I wanted at least something from this machine to live on. Although my youngest son lay claim to the playfield, and I suspect has plans for his own game.
The EM parts went to the Pacific Pinball Museum. They were glad to get some Williams parts.
EDIT: I originally was going to help the high school rebuild this one, too, but the instructor didn't want the kids poking around with high voltage relays and solenoids.

In the Fireball project, I'm currently waiting for OPP boards for the power filter and solenoids. Mezel mods were out of stock for a bit, but they are winging their to me now.
I'm also designing a bracket to hold the original switches at the right height on the playfield. And I've come up with a better design for the LED holder.

So, I made a big(for me) order from Mouser for the parts to populate the OPP power filter and solenoid boards. Paid with paypal. They promptly told me:
"To comply with government regulations, PayPal is required to review certain transactions. The payment you sent is currently being reviewed and we will complete this process within 72 hours."
Lovely.

I finished the switch bracket design. Tomorrow, I'll be printing the new LED holder to test. I'll post some pics then.
PayPal refunded my money and I was able to get the order paid for with a credit card. So, three steps closer.

The new LED holder.
Once I've tested them a bit more, I'll post the STL files.

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Yes, it is. I like these serially controlled LEDs. I use three conductor wire which makes it fairly easy to solder each side in a few seconds by keeping it with the right spacing.
Given the variability of spacing with the playfields I'm using, it's easier to make the strips myself.

The new power filter board is now together. Next up is the new solenoid drivers.
This is the one Hugh designed for the OPP system, and it went together nicely. Thanks, openpinballproj

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Got ambitious and built a solenoid driver board, too.

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If you do split off the discussion, please add a link here, since I'm interested. Thanks!

Putting the main board together now. Had some trouble last night that Hugh has already helped me with, so I'll try to wrap it up today.
This is certainly cleaner than the original plan, which mounted some of the power boards on the playfield and generally made things a mess.
Mike's Rule #1 of building stuff - Order extra parts, under the assumption that you will make a boneheaded mistake.

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After a flood of emails to Hugh and a few "AHA" moments, I now have the solenoid drivers firing consistently. Hopeful that this time, the light at the end of the tunnel isn't an oncoming train!

After I messed about for far too long, I have succeeded in finishing part one of the project. My "first flip" video is a solenoid test firing pattern.
Many thanks to Hugh at the Open Pinball Project. He's absolutely tops.

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The bits I missed:
1) I tied the wrong "ground" between the two power supplies. In my case, it needed to be V- from the 24v supply to the common ground on an ATX part supply. I connected it to earth ground.
2) double check the coil wiring. In my case, double check your double checks. Or practice desoldering MOSFETs. :/
3) the "auto fire" mechanism assumes that it's connected to the Cypress board. Otherwise, it's just a nicely designed MOSFET board. The mention of firing a solenoid without a computer coupled with the simplified switch wiring example gave me a mistaken impression of how the board worked.
Most of this could be remedied with a quick paragraph about using some of the boards without a Cypress processor. I could write up a quick example and post it.

Ok, so updates may be long in between here. I delivered the game to the high school last weekend, and they are working on the rest. As they make progress, I'll have the teacher snap some shots and I'll post then here. Thanks to everyone who have suggestions and help!
Now, it's time to move a bit quicker on my rebuild/retheme project

Yeah, I post all of my code(when it's cleaned up enough to not embarrass me).

I should note that, due to some changes at the high school, I ended up picking up the Fireball and getting it to another Pinsider, who is continuing the project.

Not from me. The project had changed hands a couple of times. Right now, she's working on another project, so this one is in limbo.