68 barracuda 383s "Driver Paint Resto"

The wheel in the top link Dave posted would work well to knock off the surface rust, as would a small handheld sand blaster with the hose stuck down into a bucket of sand. The sand will make a mell of a hess though! You're right, SPI recommends not using acid or etch primer under their epoxy. I would DA the entire car with 80 or 120, hand sand the places you can't get to with the DA, wipe it down a few times with the non solvent metal cleaner, and squirt the epoxy. SPI recommends a 1.4 tip to shoot the epoxy. You're inching ever closer! :)