Sure-grip
If you are budget minded, I think a stock sure-grip unit would work fine.What rear end is in it? I have 8 3/4 that had stock sure-grip clutch type unit and i was running mid to low 12s with m/t street e/ts. But when I put the INDY 415. I went to a spool and 35 spline moser axles, how ever its mostly race than street---- but the spool works fine on the street.