Ten years ago, it was etching primer that was the first step. But now its epoxy primer. I can see why too. Its much more durable and sticks better. No doubt epoxy primer first. Rage Gold is just fine for the filler step. The rule is anything in the 1/8" depth area filler is appropriate. Never fill with any filler deeper than 1/8 inch. Once you have it VERY close but its still a bit low, Polyester filler (glaze) is used. The idea is epoxy first, filler, urethane high build primer.. usually this makes the surface high enough with no need for glaze.
What invariably happens is, you sand in some places down to the epoxy. So lets say you are a Clutz like me and you sand to the bare metal in some places after all of this work. That's the beauty of following correct auto body standards. The next step after doing all of the previous is Epoxy Sealer which you don't sand, then topcoat.
So, short answer is Epoxy, then filler, then 80 grit, then 220 grit. It may still be a little low, so then high build primer and/or polyester glaze, then 400 grit. Once you really like the feel of it, sealer then topcoat. I never use air tools or anything power. All sanding for the entire truck is done by hand. You learn the touch and feel aspects which are so important better that way.
When I started all of this, I purchased all of the fancy power tools for sanding. Spent a little time with some of the local professionals and now I am convinced that the tactile touch and feel of sanding by hand is far better. If you go to one of the accident specialist body shops, they will beg to differ due to the time savings. Restorers who really care about the end result do it all by hand. Evercoat's Rage Gold is my filler of choice.
