I installed mine tonight - a bit fiddly but I managed to get it done. I didn't bother tying the wires back under the playfield since the new rod has a sheath.
I will say that all my wires were just *barely* long enough. The 12V, the lighting cable, and the chest rod itself have almost zero extra play. If the lighting cable were even 1/4" shorter I couldn't have made it work. As it was I had to do a lot of adjusting just to get everything connected.
I've also noticed that sometimes the chest takes quite a while to close after I lock a ball. I'm guessing the fork doesn't always immediately retract and signal the arduino?
Either way, it's working now and I love it! I still need to adjust the light, which is hard with the playfield up. I can't see what the lights are doing while I'm pressing buttons.