I'm sandblasting the frame from my 66 SS396 today. I plan on spraying on black POR-15, then chassis coat black. First off, do I have to use metal ready on the sandblasted frame? Do I have to apply the chassis coat black 5-6 hours after the por-15 is applied, or can I topcoat it anytime after? Do I need to use POR-15 solvent to thin, or can I use laquer thinner? Does anyone have any ideas on how to get a coat of POR-15 on the inside of the frame? (maybe using an old tree sprayer or something)