I know this is an old thread, but bear with me. I am refurbing a late '65 non-AC heater.
I watched this video (Autorestomod #110), some good tips, but saw something that I have not been able to find any other mention of. At 14:25 there is discussion about this bracket of some sort that is not correct, too large and blocking the heater case halves from going back together.
My heater has the exact same part. It does not have end caps.
Was this a later mod so that the end caps could be deleted?
K