out of commission, cant drive my dart anymore

Ok guys, before putting this back together, i would like to paint the inner shock tower and frame rail with something. The inner tower is pitted and rusty..not rotten just pitted and obviously i cant get down in some of the areas to sand it..Wondering what to paint this area with? All i can think of that would work well in there is POR 15..I would really like to put it back blue like originally but dont see how being its rough..