Primers?

[BRIAN]

DP is a good choice just be sure that the metal is clean as possible hitting it several times with prep solvent. You will be surprised what comes off. They make 2 activators and I just cant remember which is which but anyway get the one that takes approx 30min to set up as it sticks a lot better. As far as sand scratch swelling it can happen with the best of primers. There are a whole list of things that can cause them. If you are going the DP route use it straight through. Use dp on the bare metal than k36 than seal with dp before final color. Actually DP is a great sealer which works great on fiberglass cars as final seal coat. SEM makes agood bed liner that is tintable. Honestly I would try ncp275 which is an etch filler especially if you are going to coat anyway. Cuts down on amount of products. Good luck!!

[68protouring454]

the only time scratches swell is when rushing top coating, imho i would not use a epoxy primer as a sealer, but i am sure it can be used for that, in a resto i strip/blast car then epoxy prime or etch prime depending on car and timeline, then urethane prime, block sand 2-3 times and paint, i finish urethane in usually 600, even 800 if the color has lots of pearl and metallic in it, goodluck
jake