Engine is pulled - 273 rebuild or replacement 360 crate?

The 318 400 build article is pretty much the recipe we were going to follow. Then today we determined the 318 heads were cracked as I understand they pretty much alol are. So it’s on to the aluminum heads unless I buy a crate engine which is looking better and better.

Can the cracked Magnum heads be repaired? I think the 273 heads may be usable on the Magnum block, is this true? Just trying to understand all my options before buying aluminum heads or a crate motor.