So I cannot take credit for this idea, I read it a few pages back and I think @gweempose started the conversation with lots of good info from @TheOnlyest. I figured I might as well take some pictures along the way to help others out.
Again, I bought these buttons and they came with the important resistor required for 12v operation.
ebay.com link » 2x Durable 12mm Elevated Car Black Button Blue Angel Eye Led Momentary Switch
I also used 22 gauge wire for this modification, bought here.
amazon.com link »
Lastly, you need some .156" molex 2 position plug housing and the connectors that go inside. Optional is making plugs at each trigger assembly. I used .062" molex round pin stuff.
First step is to detach the 2 pin switch connector (green and white), the 7 wire connector attached with Z connector (this needs to be removed at flipper switch opto board in addition), and the green grounding wire attached to leg mounting plate.
Using I think a T25 security Torx bit, remove the 4 mounting screws connecting the assembly to the cabinet, no need to remove the clam shell half at this point.
With the assembly on your workbench, remove the two torx security screws holding the halves together. If you are nervous about this work, remember, my kids are helping its that easy.
Remove the white and green switch wires from the switch assembly, note there is NO diode on this switch. I will check the manual to see if the diode is elsewhere or if this is a direct switch not part of the switch matrix.
Now you need to remove the small phillips screw holding the micro switch into the switch housing. Remove the switch and keep the mounting plate and the lock washer, my new buttons did not come with a lock washer so I reused the old one. Keep all the switch components in a baggie in the coin box for later use or if the new owner does not like the new buttons. I always keep any original part I remove from a game.
Assemble the new angle eye switch. Do not worry about using the o-ring supplied with the new button. I orientated my button so the "+ and -" LED connections were on top and bottom with switch connections to left and right but it does not matter. As you can see, a bit more room in the trigger housing with the new buttons.
It is very important that you use the supplied resistor inline with the LED. This is used to drop the voltage for the LED. It can be wired to the + or - terminal, I chose + terminal. Add heat shrink to the stripped wire and pre-tin the wire leads and contacts on the new switch, this will help with soldering them together. I first soldered the resistor onto the "+" terminal of the button, then the negative wire to the terminal opposite of the resistor. Lastly, I soldered the positive wire to the other end of the resistor.
Now you can re-attach the switch connections. The old switch had a normally open pole and normally closed pole, the new switch is ONLY normally open so the green and white wires can be attached to either of the other two connections. Williams did not add heat shrink to original connections but we are not worried about tact time or assembly cost so add some heat shrink. Even if we are not professionals we want to act like them.
This is good time to bust out the multi-meter and check to see if the button works and nothing got damaged. Alot easier to change something now then when the machine is all buttoned up. Using a heat gun or lighter, shrink the heat shrink once you verified the switch is working.
Place the new switch assembly back into the housing and route the wire similar to as shown. You just do not want them interfering with the trigger button action.
You can now cut the other end of the power wire and terminate with a .062" molex connector of run it right to the coin door interface board. I chose to use molex connectors because it will be easier to remove handle assemblies later on. Remember to cut leads long enough to clear the flat mounting plate on the inside of the cabinet. Make sure the new power wire is routed into the grooves along with the other bunch of wires, you do not want to pinch the wires during assembly.
Reassemble the handle assemblies making sure to not pinch the wires. Route the wire bunch back into the cabinet and re-attach the handles to the cabinet. If you game is home use, you can switch to not security torx hardware and swap out for standard hex head button screws.
Measure out some wire and terminal with the mating molex connectors for handle assemblies (if you added connectors). I used 22 gauge wire which was small enough to fit two wires into a .156" molex connector so I could make a wiring harness.
We want to attach the power wires using a 2 position .156" molex connector to the coin door interface board. It has a spare 12v supply I can only assume would be to run a ticket dispensing machine or bill validator. Positive to "12v" pin 4th from bottom or pin "1" and negative to "PWR GND" pin 3rd from bottom or pin "1".
You should be all set, turn power on and marvel at your work.