I could not find any of the Non addressable chips anywhere to even consider making my own, so I ended up making a string of similarly sized
addressable led boards, controlled by an Ultimarc nanoled. It seems to be working, so far. I am also using 2 pacleds64s and they are all working together and running with ledblinky, although I have not tried to do any individual custom programing with it yet.
I make it in 3 sections, for easier maintenance and assembly, and joined them with screw caps. I found solid wire to be by far easier to work with than stranded. I used 22g but tested some with 24 which I am guessing would be ok for this number of buttons and length of run.
I bought a sheet of 100 so I could practice. I recommend keeping them partially attached together so you can hold them with some "helping hands" while soldering. Hands free magnifier was invaluable. Not sure I could have done without it. I put a good amount of solder on each of the 6 attachment spots first. then did the individual wires one by one by touching the tip of the wire and the solder spot at the same time, and sliding the wire into place. The second row I did with the bare wire already partially bent to make it easier to get over the top of the first row, making sure there was plenty of gap and no bridging. Also making sure the plastic jacket does not melt and cause a bridge.
I am kind of making this up as I go along, so anyone feel free to correct me if I am wrong:
The first LED 5V connects directly to the power supply. The power supply ground connects to both the Nanoled ground and the ground of the first LED (I connected those 3 wires with a screw cap). The Nanoled data pin connects to the first LED "Din" (there is only one active data pin on the Nanoled). All other LEDs connected in order after that. Longer runs could potentially need an additional 5V boost inserted somewhere along the line, but I have no idea how to calculate or estimate that.
I ended up doing some initial testing with a Arduino to make sure everything was working.
Practice:

First row attached:

Second row attached:


project link:
http://forum.arcadecontrols.com/index.php/topic,163631.0.html