Order of assembly? From a bare shell

Epoxy primer DTM will stick to even cat chit. Worth the $, and you do not have to buy the highest price stuff out there for it to work. Then covering with Rustoleum is a cheap and good avenue. You can buy a spray gun cheap, that shoots a qt. or gallon of undercoat like the factory used. Some undercoats can be painted also.
Like said, I hope to have a lift by the time I hot 90!!
Don't it make you feel good to see the bottom of your car so clean and pretty!! Ya better hurry up, winter is just a week away up there!!??????