Ok... here are my thoughts on your project... if I were doing it...

I would sand that puppy to get all the rust off.

Like the other writer said... I would be using an agressive grit for the initial ripping down of the original paint and the rusty surface areas. You might use the 60 grit for the initial ripping... but I would then do a 120 or 180 after just to minimize the 'scratches' that the coarser grit will cause. After all, primer or paint can only fill in 'so much' of the grooves that the coarser grit can cause.

I would think that the truck might be a good candidate for two coats of primer... This will give you more then enough primed thickness to work out the wetsanding etc and not find yourself taking the surface down too thin.

I don't think you should look at using aerosol bombs to spray primer on to the body. You would be better off using a roll on primer. This will give you a far thicker layer of primer and better coverage.

My personal preference, having used about five different types of primers... is the primer designed for Brightside paint. I was blown away by how much better it covered the body when I rolled it on. I think it has a higher percentage of pigment material per drop..

On the other side of the debate, I would be negligent to not mention that there are some practitioners here who have gone straight to the paint stage and bypassed the primer stage. After all, Rustoleum/Tremclad and Brightside are quite capable of going directly on to metal.

But I like the use of the primer in order to get the entire body up to one uniform starting color. As well it gives you an initial idea of any nicks, bumps, defects etc that you might want to do a little further bodywork on before proceeding to the painting stage.

One other fast HINT here is that if you are going to go the primer roll on route... cut your primer with 50% of the paint color you are going to use for the body painting. Let us say you are going to paint that truck red. The canned primer you are going to use is gray. So make a 50 / 50 mix of gray primer and the red paint.

What this will do is lay down a 'starting coat' that is closer to where you ultimately want to end up. The same story would apply to whether you were going white, black, green, blue, etc. Think of this primer hint as being like in a 500 yard dash for your project and you are cheating by starting 50 yards further down the track when the race begins. Its a cool cheat.

I would then primer the entire vehicle so that the whole body is one uniform color. This will make the addition of the paint layers much more uniform. This is especially important when dealing with a body of many colors at the start.

Yes... you can wet sand your primer once it has fully cured ( dried ). BUT what I would make sure of is that one I have completely wet sanded the entire body I would then let it fully dry. I would not want one ion of h20 left clinging to the primer.

And I don't think I would add any soap to the wet sanding of the primer. I would not want to chance any detergent being left behind attached to the primer.

Once you have done the above steps and waited a few days for it to fully dry... I would then go over it with a very very light dry sanding of the primer. This is just to give one final smoothing out of the primer.

Ok... so let us assume we have made it to this stage, I would next go to wiping the entire primered body with a slightly dampened CLEAN cloth ( dampened with mineral spirit ). This is to get any remaining foreign matter off the primered surface.

And AGAIN... let it fully dry so that any of the mineral spirits that were used to wipe down the primer have fully and absolutely evaporated. You don't want any of those mineral spirit molecules left clinging to the primer.

At this point you should be 'good to go' ahead with starting to do the roll on paint job. And one of the benefits of having 'rolled on' your primer is that you will have developed your technique for rolling - and you will have become familiar with all the surfaces and nooks and crannies of the body that they will be later painting.

Don't know if this helps any. But this is basically the recipe I would have done if I was starting with the truck I saw in your pictures.

Best of luck and welcome to the club

And out of curiousity... what color are you going to go with.. ?

Marq