I guess I did leave you guys hanging on this. Life has had me very busy.
Well here is the summary:
-I remember popping the heads off and seeing some nicely burnt valves. Machine shop eventually told me the Valve seat was destroyed, and valve guides were wiped.

-Slugs 5 and 7 had impact "scuffs" on the top....strange that I never heard or felt this happen. Maybe reused pistons? (I had bought someone elses motor, HUGE MISTAKE....will never do that again)

-So I found some 781's that had never been worked over. New everything and a clean up. The heads just didnt work with the puny cam. When I bought that disaster of a motor in 2003, I was told they were decent heads (This was my first big block, and like a MORON I didnt even bother to get educated. Plus I was buying from a "friend")

-So I pull the 781's and sell them off for what I paid for the whole motor!!!!

-Winter 2004 I yank the motor and take the block to a REAL FRIEND and started the cutting.

-Almost 4 years later I have a 496 roller motor with ProTopline heads, 294H Comp making the idle choppy, Forged everything.......the list goes on and on. Awsome street motor. And have never had a problem since. Still no leak down after all this time. Of course I have become a lot smarter about spinning wrenches also.

I built this motor to handle a 300 shot of juice (It will never see that)
As of now this motor is in my 73 Z28. 3800lbs. 116 mixed with 93 from the pump. No hose or other power adder.Just motor. 560hp/602tq....I still havent slapped her on a chassis dyno, but I really dont care to. It gets driven daily and raced on the weekends. The trailor is there only for break downs, and to lug around slicks and tools.

Thanks to everyone that has helped me through this old nightmare, and some of my other 496 questions from this same time frame. I know there has been some sort of drama about Streets.....but I am forever in debt to him. Again thank to everyone