I would say go with the spec stage 2 and pressure plate get the mounts and get a lightend flywheel i have a fidanza in my z24.
As for you exhaust i would say get the header anyway but a resonator is going to fix that sound.
You need at least a 12" resonator
A lot of people on the org have the spec clutches and like em. Generally speaking a 4-1 header is better for high end horsepower and a 4-2-1 header is good for midrange.
^^^ not always true
the pacesetter header is a long tube , and has the benifit of the better mid range of the 4-2-1 , plug better high end
4-2-1 headers work in a narrow rpm range
get the stage 2