Got a set of irons at the yard from an unknown year 12A, what are some defining characteristics between years? Also there is some rust on the faces of them, is this going to be an issue in using them or can I just get them resurfaced? I'll try to get some pics up later on of them, Im plannin to bridge them or just use'em to practice on if they are junked.

 

if the water inlet by the temp sensor has 2 inlets it is from a 83-85 engine.