On the same repair, the water heater was pulled, to do the repair.
When it was out I noticed three types of caulking?
1. White Proflex on the outside
2. Grey Butyl tape on the mounting bezel
3. Looks like Clear Silicone on the bezel to heater frame.
The bezel looks like a crimped on stamping.
The heater is cleaned and painted, ready to go in, when I find out what is the third caulking.
The third caulking was not in good shape, and also was used the seal the folded corners of the water heater frame.
I am thinking this could have been my water source.
Bob