My body is completely disassembled and I will be putting full floor pan/firewall in soon. My question is regarding all the interior crevasses (inside of door, inside rear 1/4 window cavity, underside of roof skin,etc.). How do you prep these areas. I have a pressure blaster and soda blaster. Do you sandblast (wow, messy) or simply wash and scotchbrite, then paint. Do i paint then undercoat or just undercoat. There are so many products out there its confusing. Rust encapsulators, rust converters, metal preps, marine cleans. I called Eastwood and they basically answered "yes, you need that" to all of my questions. Needless to say I don't want $2k of unused cans and jugs setting on my shelves. Thanks for the help.

Let's see...if you've got rust, take care of that first by using some sort of convertor. Then clean as best you can, making sure to get off all oils and moisture. If you sand blast you will be fighting sand dribbling out for years. If bare metal, you can use an etching prime(some will argue that it's old school and not really needing to be etched). Prime and definitely seal with paint. Primer will eventually absorb moisture if not sealed. I wouldn't sweat the paint finish so much on areas not seen unless you just want the practice. I'd finish all parts before installation and then go back and address the ares that were damaged during the installation from welding and such. Probably be fine with a wire brush and rattle can at that point. Eastwood make paint cans with a spray tube to get in areas close up that you can't seem to get at any other way. All you can do is what you can do.