I'm working on a Robotron project and need to replace the upper and lower plastic vent grills on the back of the cab. These things are so brittle they crumbled in my hand. I found some perforated aluminum that's real close to the original and plan to shear up a pair for my game. I thought I'd see if anybody else needs them and I would make a few extra while I'm at it. I assume all the Williams cabs use the same grill. You would have to paint them black yourself. Should make a nice replacement. Figure $12 a pair plus shipping. LMK if you're interested.