Porsche GT2

I have just been doing F/A-18's since getting back into doing models. After painting the inside of the intakes white, what is the best way to mask them when you are painting the rest of the plane ?

I'm tired of buying and using compressed air in a can. I've decided to buy a testors ac 200 compressor. Is this a good first compressor or should I go with a badger? Any thoughts? Thanks.