My 79 has a non stoc cam, heads, intake and carb. My car ran great using Motor craft AR52 plugs. I am having trouble finding them locally and would like toswitch back to AC delco plugs. Can anyone tell me what Ac plug would be the closest match to what I have. Thanks in advance for any help.

Here ya' go - http://sparkplugs.com/ click on the 411 and you can find out more about spark plugs than you ever wanted to know. :)