[vancelot69]

hemi43: Yeah, that makes sense. Thanks for the education.

So, it wasn't WOT, but it felt to me like I was hammer down and it was revving pretty high (without having a tach to know for sure) when I drove it last, with an SM465 doing 60-ish, 33s, not sure of the diff gearing, I assume stock, and the SPID plate says 3.73. Another thing last time I drove it, it was about a 35 mile trip, 80% on highways. About halfway through, while on the highway, it started losing power and slowed down to about 52 and was running rough. After a moment, it straightened out and was ok the rest of the drive... And, I've been hearing an almost constant lifter or valve chatter. Sounds to me like all of this is related.

Do you think I really need to do main and rod bearings and rings, or do you think I can get away with just gaskets and seals?

Thanks again!