Okay gang, she's done! I'm happy to report that it is possible to RP a P2K S3!! I was able to fit in a Keep-Alive (K-A), a Speaker and a RP LM-3S module without unwrapping it. I did angle the corners on the 6 pin side just for a teeny extra bit of room (see Step 3 below).
I'm sorry, but I don't have pictures. After fighting with the shell 5 times to get everything in, I'm not opening the beast up again unless I really have to!
General gist:
1. Toss the weight.
2. Toss the P2K 8 pin plug, you'll be hard-wiring this bad boy.
3. Remove a teeny bit of the thickness from the back of the side numberboards - rotary cutter in a dremel does this right quick.
4. Cut a piece of .030 styrene the width of the RP Module, but not the full length. This will be your support for the RP module. Screw it into the upright frame post at the nose and tape the orange wire to the underside of the styrene. Orange wire grounds to frame through the screw as per factory setup.
5. Tape RP module to the styrene, with the 6 pin plug to the front of the unit, just clearing the screw. Speaker wires and K-A wire (2 brown, 1 yellow) are taped to the top of the module, between the module and shell.
6. Make all your wiring connections.
7. Double-sided tape the Sugar Cube (11 x 15) speaker to the shell above the rear flywheel. Speaker fires upward. I've drilled out the stack, so this helps let the sound out.
8. Double-sided tape the K-A (I used a KA4) to the shell behind the speaker.
9. Remove portion of firewall of interior to clear K-A.
10. Put everything back together and pray you don't have a wire rubbing in the wrong spot (ask me how I know this...)
11. Load sounds and do the motor setting. For some reason, I had to tell the LM-3S that the motor polarity was reversed. Whatever...
12. Enjoy!!
I didn't tempt fate and try to install working lights. Unit has MV Lenses front and rear. One day, if I get brave or stupid I may try to add working lights, but I'm happy with her just as she is. All she needs now is a Alco 539T Ultimate sound file. I'm content with what the 539T file for the time being.
FYI: This is not a quick conversion. Not counting all the planning time and false starts trying to save the weight, this took me half the afternoon, plus a whole NHL hockey game to do. Might be a little less time if my team wasn't smothering the other team. 5-0 Win!!