I've Heard of Painting between the lines but, can this be done?

I have a 68 Charger as well and it is from Missouri, rust bucket. I was wondering how to attack the rust between the metal layers in the hood and got a great answer here. I definitely need to check out the eastwood internal frame coating. Folks, I appreciate this so much. It has been driving me nuts trying to figure this out. The car has almost no rust anywhere except those frame rails and a under the speaker shelf. Go figure. Front frames are great.
Sand blasting would be great. The car is on floor jacks. There is nothing under the car. Entire front and rear suspensions including rear end are out. Money is tight and I have no choice but to do it this way. Maybe when I get to the Charger