There is nothing wrong with doing your project the way YOU choose. You are doing the truck a favor in any case. Being in the US and having a nice shop, also being a little picky with no time constraints, here is what I am doing right now...
I have my frame on a rotisserie. Easy to do. All you do is purchase two engine stands of the same kind, cut it apart so its at 90 degrees, add a 1 inch acme screw (18 inches) and now you can raise/lower as well as rotate EASILY your frame. You also have to connect them together otherwise you have problems you never envisioned. In any case, being able to spin the frame to any position easily makes your decision on what to do next pretty easy. If you do more than one frame you need this. Its also good for sandblasting, painting, prep work, everything.
In this case, I had two back operations about 5 years ago that left me with 4 titanium rods, 13 screws and 2 plates in my back, so the rotisserie is paramount. I had already painted my frame, dolled it all up with a nicely painted 261, open driveline, OD, etc. But upon looking it over with todays standard, it looked TERRIBLE. Runs, dents, pits, misery everywhere.
I chose to go ahead and NOT sandblast again, but rather just rough up the existing paint with 85 grit and start from there. Keep in mind it WAS sandblasted to begin with, then etching primer, then epoxy primer, then urethane topcoat.
So in February of this year, I started with roughing it with 85 grit. Keep in mind what we are talking about here. EVERY rivet, every channel, every impossible to reach area was roughed with 85 using various sticks with sandpaper on it. After it was roughed, I put another coat of epoxy primer on it. Since 85 makes most of the frame bare metal again anyway, not much mil thickness involved.
Once epoxy primered, LOTS of rage gold plastic was applied, then almost all of it sanded off. Imagine the fun around each rivet which may or may not be level with the steel its joining. Imagine better yet, the center cross member (just behind the cab) with lots of rust pits that needed to be addressed. Not to mention the channel at the front of the frame. All of this was sanded with 220 grit. Once this was done, about the end of April, and trust me I work 7 days a week on this project...
I then painted it with Urethane high build primer. It was nice having it one color again. Once this was done, sanding the whole thing with 400 grit dry was the next step. I researched this issue and listened to MANY experts who didn't always agree. Since you're next step is Sealer, and you cant sand sealer, 400 grit dry is all that is necessary for the frame.
So, we start all over sanding every rivet, every channel, every nook and cranny with 400 grit. At this step, we are holding a high intensity light on the work at different angles to make sure you have each rivet, all 360 degrees of each rivet, 100% flat and even. You haven't lived until you have tried this!
Its July and I am almost finished with the above critical step. Once I am finished with the 400, its cleaning the whole frame with DX330 metal prep cleaner to prepare for Sealing. The sealer is an epoxy based sealer that gets you ready for topcoat. The topcoat is applied no more than 72 hours after the sealer. So, maybe by next month, this frame will be done. With this careful of work, I am using full gloss single stage urethane. If its not REAL darn PRETTY, im gonna be disappointed. LOL.
