Tinman speaks the truth and you sound like your inclined so don't shoot from the hip. Don't start it again until you have come to an educated decision on the cause of the squeek, tap, pop, clang, bang, etc... Start with the easy stuff, pull plugs, remove valve covers, roll by hand, verify correct valve accuation, timing, etc... Should roll with fairly consistant ease throughout the complete revolution. Just MHO. Theres a wealth of knowlage on here, they should have you goin in no time. Good luck.

Well, he brought it to a mechanic, so far best compression was 90 out of eight cylinders, pulled valve covers, valvetrain is covered in rust, and bent pushrod(s), also loose rockers supposedly. sooooo waiting to hear on plan B.

Regarding the previous "top end work" were the original heads used or different ones installed? If the original heads were used were they pressure tested? The cooling system can corrode through the water jacket and give water issues like described. I had this happen on my 454 mag HO. My squeaking was broken rings on one piston where the water got on top and hydroed it.
A leakage test can determine if the compression loss is heads or rings.

Hopefully, it sounds like the problems are limited to the top end.

Ditto on the oil filter opening method, ie,definately use tin snips or other non fracturing, grinding or cutting tools as they will contaminate or skew the reading.

How you makin out 007?

Just remembered this thread, he ended up needing a new engine and went with a Jasper, we had some good offers from some board members here but he wanted a "warranty" engine just came in on Friday, so hopefully he'll get some use out of it, Thanks for all the responses.