Hi Mang,
I was about to post the same question on here. I still use many 'classic' ADJ effects in my setups and after all these years a few of the units are starting to show a little wear and tear! My concern would be making sure the paint can handle the high surface temperature generated by the halogen lamps. Either way, these forums seem to be pretty much dead. Between all the posts with no replies and other threads that are just random adds, I think it's safe to say we won't get an official reply, let along a reply at all. It's a real shame... A few years ago this forum was a great place to come for help and suggestions with ADJ products. I'll post back if I ever get an answer to this!