Get an exedy mach 400 11" clutch (the 01-04 unit) and upgrade to an 11" flywheel. "Stages" are advertising gimmicks and mean jack ****, go by the torque rating. The clutch I mentioned is good for 500ft lbs and is $230 on AM after 6% off. Pedal feel is lighter than stock too. You need to do the flywheel with the new clutch anyway so might as well go to 11".
As for the throwout bearing, the links provided were to Ford Racing. Those are not the OEM units, the OEM ones are different. Go to a dealer and get the oem pilot and throwout.
2000 Mustang GT Steeda #0048
Just because I give you advice, doesn't mean I know more than you. Its just means I've done more stupid ****.