it might (probably will) fit in there ok, but you defeat the purpose by having less clutch disk friction area. that would be the worst of both worlds. if your stuff is all new, try it, its not exactly hard to pull the trans and chuck a new disk and hd pressure plate at it if it slips on boost.

careful lightening, take material from the outer edges mostly (most inertia), leave enough meat on the back of the friction area to absorb heat under heavy use, and leave enough meat in the middle to avoid it coming through the floor and taking off your leg. machining to cast iron flywheels should be kept to a minimum really. the right way to go if you want light is to get a fidanza or similar. thats why i took a bare minimum off the back of mine, not so much to lighten it, but rather to smooth the casting out and try to eliminate any stress risers. besides, the benefit of lightening a flywheel is so small in reality. its barely worth it at all (not saying i wouldnt, but...)

fred.