LA heads on a magnum block

I think his best thing to do is find another LA block. Hes just a kid and doesn't know hardly anything about cars. And he is working in a all chevy shop so they cant help. Their the ones that told him the blocks were the same. He put his old la cam in the mag. My son went over there and helped him get it timed and started it up for him. It sounds good except no oil upstairs. We squirted oil on the rockers and it ran good and sounded pretty good. Thanks for all the help.