OK, all of the credit goes to @mageek for this one and for basically hand holding me through this process.
Here is how you create a power switch for the phone screen, so if it blanks on you, you can turn it off without turning the whole pin off.
First, remove the yellow (hot) wires from the phone power molex connectors. You can leave the black (ground) ones in. You can confirm which is hot with a multimeter. My multimeter read 24V going to the phone.
I didn't have a molex removal tool...but 2 sets of bent paper clips (I used 2 together to make it stronger) make an easy and cheap replacement tool.
Then...I took a pair of wires (I used 20AWG door bell wire), and on one end, I attached a set of molex connectors (male and female). On the other end, I attached an extra playfield microswitch that I had laying around. You want to solder one wire to the common on the switch, and the other to the Normally closed (NC) blade.
Next, insert your molex connectors into the yellow wire molex connectors from the phone power. Test to make sure your switch works.
Once verified...then heat shrink your molex connectors.
I went ahead and took my wire to the underside of my pin near the main power switch. I used foam tape and gorilla tape to attach the wire. It looks ugly, but I'm sure someone else could come up with a cleaner looking attachment method. I wanted it on the outside, so I could just trap up a ball, reach down and flip the phone power. @mageek had his switch on the inside of the coin door, which is probably safer (keeping all power inside the pin), but you would have to wait to launch a ball so you could take the time to open the door (killing flipper power) and activate the switch.
This mod is completely reversible. When you want to remove it, just cut the heat shrink off and put the original molex connectors back into the original power connector.
Seems to work great so far. Only concern I have is if this little microswitch has no problem with 24V power in the long run.