I've been using POR 15 for about 10 years and it is a great product, however I have had little sucess with painting over it once it is cured. It comes in sevral colours and if you want to use it was an under coat go with the gloss black, it will dull over time but still look good, if you try to paint over it the paint will eventually chip and flake away.

The two thing I've found that my sporty has in common with my MG's is they both like to attract rust and the electris are less than perfect, i swear when MG went tits up in 82 all the enginers moved to Korea!