after a lengthy search, I believe 1990 Actys, Do Not Have TTY head bolts. Manual covers torque sequence and value. But no mention of a final degree turn, like you do with TTY bolts. Still I can't find anyone who has stated that they have reused their bolts. I don't have a problem buying new bolts, but why should I, if I don't need them. So to anyone reading this that has installed a head, did you use new bolts?