I'll add my two cents worth of info for the paint. If you use the cheap stuff like Rustoleum or even the rattle-can brands, the paint will not last more than a year or so. The "prep" work is critical, which includes dent removal, cutting out any rusted panels and replacing with new sheetmetal, sanding, and quality primer and paint. There's several types of paint, including enamel, laquer, urethane, etc. The best quality paints are from such folks as DuPont or PPG. Price will range from $100/gallon on up. It should take about 1-1/4 gal. to paint the Bronco. The actual paint is your basecoat, and then you apply clearcoat over it. Just use the type that calls for a clearcoat.
If your paint is decent, you can prime right over it after sanding. If you have rust, you need to remove all of it, even if it means sanding to bare metal. That's where the self-etching primer comes in. Remember that if you paint over existing/factory paint or primer, there's a chance that it will bubble up or peel off and take the new paint with it. Talk to a couple of body shops and ask lots of questions while getting an estimate. You'll find that the good ones will charge about $3000 for the entire job. You can cut that down to $400-$500 by doing it yourself, as alot of that cost is labor and prep. Cleanliness is number one in a successful job, and you may even be able to rent a paint booth.
I was lucky enough to have a friend that retired after 35 years in the body & paint business do the work on my Bronco. He works at home now, just doing show vehicles now and then. I learned alot of info from him and got a great paint job for $1300. It has 4 coats of paint and 4 coats of clear with a sealer & hardener.