Evaporust by the barrel?

I was thinking about the same paint I use on the inside of the block, Rust-Oleum Rusty Metal Red primer. However, with all the "windage" I probably should not even paint it at all. I am curious if the paint would survive for long in that location. In the past, I did not have any problem painting the cast portions of the block, but the windage tray might be another story alltogether.

P.S. This kind of reminds of the time I deepened a stock oil pan and pick-up 2 inches, then attached a home-made baffle with epoxy. The epoxy let go sometime before I tore the motor down later.