I'm with Dave Andrews. The only reason I would consider this is for amber turn indicators.
I'm an EE, so I think I could handle the wiring
I'd need to look at it a bit, but I suspect you change the wiring at the brake light switch so the existing wires going to the rear brake/turn filament would only go hot during a turn or emergency flasher. You could then drive the stoplights using the third brake light.
I can look at it a bit more if some were interested.
I don't know thing one about plastic fabrication, but I could probably figure out the electrics.
TB
Tony Boner Personal: 98cdw27@charter.net Work: tony.boner@sun.com Saving the computer world from WinBloze as Unix/Solaris/Java Guru http://www.sun.com 1998 Contour SVT Pre-E1 618/6535 Born On Date: 4/30/1997 Now with Aussie Bar induced mild oversteer.