81 camaro 267 delema...need opinions

I just bought another 81 camaro w/ 267 v8 (i was told had a bad knock) for a parts car for my 81 z28, i paid $500 for it, i got it home, drained the old oil (which had been in for at least ten yrs) the ugliest sight, oil resembled a slightly runny version of gray honey, but anyway, i got it sorta got it running aand with some jerry rigging got it run ok, it was knocking loud as hell, i was under the hood manually operating the little 2 barrel carb, and about half throttle she was belorin pretty good and suddenly a few clunks and bangs later she's done. if i had to guess it sounded like a connecting rod broke but in not sure because i havent heard more than 2 v8s blow up before, but as of now im shit outa luck. it was supposed to be a parts car but i want to give the old girl a second chance, should i rebuild?