I when bomb canning generally use a high temp gloss black. That’s what OEM was basically.
If you don’t want the black paint flaking off in like 2 years, clean the s*** out of it and get it good and dry. Then first hit the bare brass with some self etching primer, then a top coat of a sandable...
Ding ding! Self etching is for bare surfaces - metal, fiberglass, some plastics. It's there to provide a hold for the next layer of primer to adhere to rather than the bare material. You really don't want to apply your paint directly to the self-etching primer. It can handle a little rust, like...
Nice rig. Need more pics. Underside, interior, engine bay, etc. Just some honest feedback, the way you worded the coolant leak sounds like a cracked block. Needs pics of it.
GLWS
Apparently it's impossible to exceed the weight limit of 70 pounds on their small flat rate boxes even if filled with the densest substance on Earth but damn people sure do try!
Awesome! So lets read the tea leaves here...
The overlay is still intact, no copper showing. So not put under heavy loads for long periods of time and/or you have low mileage. If copper was showing, it's likely they are all like this and your new rear main would be leaking again in short order...