Im running a 9" ford in mine that has been cut down. Do you already have the wheels, If so what is the backspacing on them? Also how wide is your 8.8 mustang rearend? Let me know these few things and i will try to help you out with the correct setup.
One more thing....is your s-10 rearend the 2wd or 4wd unit? Ive got a bunch of chassis measurements for these things just need to dig it all up.