Pearl White is a tri-coat system (base coat, mid-coat, clear coat). But if you don't necessarily need the pearlescent effect, you can use either a base-clear or even a single-stage. Almost all urethane products will hold up to gasoline fairly well. You can get them in 2-part rattle cans now, and although a bit on the expensive side I would think that you could cover the entire engine compartment with two coats using 4-5 cans. Make sure to clean up and degrease very well, and use primer before paint.
