At the time I was fixing many cracked aluminum heads in Ford Escorts by having them welded. A shop next to me had a Chevy Luv which is really an Isuzu. The shop insisted that it couldn’t be fixed because the crack was through an oil passage and the clearances would be too tight after milling the head flat. I took the head to my head guy to be welded and he drilled out the oil passage and pressed in a steel tube to take care of the crack in the oil passage. I gave the head back to the shop to install.