Thanks, Ironracer. The funny thing is that this is my fourth slant six engine that I've owned, going all the way back to 1977. In all those years, I never once noticed the fasteners that I just finished replacing. My current engine, for example, was rebuilt by a professional engine building company in Tacoma WA in 1988. When the shop in Portland OR that installed the replacement engine re-attached the manifold set, they just used a bunch of hardware store nuts and lock washers instead of the correct fasteners that I've mentioned in my article. And the engine has ran great since then. No cracked exhaust manifold. But I'm still glad that I got the right stuff in the right places. Those brass washers, triangular washers, domed washers and castellated nuts are getting really hard to find. I was lucky to score a virgin complete set off the donor car that I mentioned, which had just come into the salvage yard when I found it. Had I waited a month, all those nice goodies on that motor would have been gone.