Yes, I'm going OEM. PAPI Seattle has purchase Yale and I was referred to their parts people. They have been very helpful and have located the head and manifold gasket seperate from the full overhaul set for me. At my suggestion they will get the torque spec. from their service dept. if that doesn't come with the gasket.

On the TTY topic, I have done a lot of research on this topic and for my auto repair business. I won't go into all the details but the number of times the bolts have been torqued is "a" determining factor in replacement. My general rule is I reuse them if I know for a fact that they have only been previously torqued at OEM assembly. Beyond that there is no way of knowing how often how much they might have been stretched.

One TTY factor, I came across while searching, TTY bolts seem to be confined to aluminum heads or some laminated head gaskets. I think the Yale (Mazda) diesel has a cast iron head.