I just got a cobra intake and I want to know what size TB to go with. Its a 87 w/ SD. It has Mac headers, O/R Hpipe, flows, & 4:10 gear. Since my valve covers are leaking, Im going to replace them as well and add 1.7 RRs also. What size TB would you guys go with?? 65? 70? 75? Ive always heard...