Well more progress made this weekend. The main bit of news is that the programmable LEDs (WS2811's) are mounted and working!! This was real 'heart in the mouth' stuff as I had to first fit the hollow T-molding (I've never fitted T-molding before).
The slot was really tight and needed sanding out first. I realise that the T-molding needs a knock or two to get it to seat correctly but was paranoid that knocking would damage the LEDs.
So, I measured / cut / fitted the T-molding without the LEDs first. Then I used a pull-through and pulled the LEDs into the T-molding (after soldering tails on to the 'cut to length' pieces). Then I tentatively fitted them and just kept my fingers crossed!
I'm pleased (and amazed) to say - it worked! I set a quick test program up in the Arduino to just light each bank of LEDs red then green then blue to test that they worked.
I've also mounted LEDs around the inside of the light gun holder (this is just a plaster tub that clips underneath the slots for the light guns). I'm hoping to be able to light that up if a light gun game is selected.
I fitted the "static" buttons along the top. I've gone with 1P, Coin/Shift, Vol up, Vol down, Menu, Play, Pause, Exit, 2P, 2P Coin. (A big thanks to SlammedNiss for the decals).
I've still got lots of wiring to do next and also a long list of small jobs but another good weekend should break the back of the project hopefully.
:-)