LA vs. Magnum block

The Magnum cannot replace the LA if you are running LA heads. At least, not without drilling the passages that run from the decks to the #4 cam bearing journal. (not an easy job...It's about 4" long, and you're aiming at a journal less than 1/2" accross, and a hole in the bearing less than 1/4" in diameter.A miss means top end oiling issues. It's cheaper for them to buy an LA block. 360s or 318s are NOT hard to find. I wouldnt accept that replacement myself. I think the Magnum uses a different rear main seal...the #5 main cap may be different. I am not sure about timing covers..but I think you're OK there. On the upside, you now have the provisions for a factory hydraulic roller cam. I would maybe work it so they buy the cam stuff and drill the holes....lol. Magnum blocks are cheaper than LAs at this point.