Any upgrade combination is possible. The reason I leaned towards the SPEC 1 kit (over SVT components) was the fact that the SPEC kit came with the alignment tool -- a small, but critical piece!
The price of the SVT flywheel is very attractive ($95) -- the slight weight reduction over a standard Duratec MTX flywheel is minimal (a bonus is the slightly faster throttle response). I didn't want to go to the 'extreme' and pay a bunch for a super-lightweight flywheel; besides, I've heard that a little bit of rotational mass ain't that bad (in a way, I think this ties into the whole DMD modification -- a little rotating mass helps smooth things out a bit; i.e. potentially less rollover noise).
To answer your question, a super-lightweight flywheel isn't going to bring about astronomical engine power gains, so any clutch (SVT, SPEC 1, or others) would be able to handle the 'extra power' brought about by the flywheel.
