I've unsuccessfully tried to determine if shields were original from the factory. As I mentioned before, my starter is an original that has been repaired/rebuilt three times. I also know there was no shield before the third repair because I considered adding one I purchased to help with the hot start problem. Before I added it, the starter failed entirely. I find it odd that Mr. Goodwrench in the 1972 and 1980 repairs would have tossed a factory shield. Also, so far, I have found no reference to a shield in documentation.
They are probably a good idea with the heat issue, however, does anyone have evidence of a shield being factory?