Jimbo, I'm no professional, and this is my first truck restoration/modification... so take this as just someone else sharing their personal technique.
1) strip areas that need metal work, do the metal work, strip the rest of the truck
2) use an epoxy primer (i used the Summit Racing EP (covered well and sanded decently with 220 then 400)
3) any filler work needed
4) reshoot primer over the filler, wait the recommended recoat time, shoot over the filler areas again (since it absorbs into the filler), wait, shoot over the entire cab
5) sand to 600 to remove any imperfections
6) seal (i'll be using reduced epoxy)
7) paint
my truck looks a lot like yours with filler in several different places
Last edited by GMJager; 08/10/2015 11:38 PM.