You should never reuse TTY (torque-to-yield) bolts. Buy the FRPP head changing kit , like $120 and you get 2 head gaskets, 4 exhaust gaskets, head bolts, and bolt lifters for install. http://www.dallasmustang.com/prod/9911
+1 on the ford racing head changing kit, also you get a new dipstick tube, a least mine did, I got mine from Late Model Restoration for $104.95 plus shipping.