The best ones seem to be casting #'s 2863549 (RH) and 2863553 (LH) these are the ones being sold (new) at Yearone for $599 the same ones are on Ebay for the same price (used) so I think I will go for the new ones, old ones could be warped or have hidden cracks about to open up they look like the ones on the T/A and AAR ? don't know if they were on plain 340 4bbl E Bodies in 1970.