I have never owned my own truck, but my dream is to find the perfect old truck.
your first task is accepting that critter don't exist. You may restore it to a thing of beauty but under the shine somewhere rust is hard at work.
I bought an old Tradesman previously owned by Philadelphia Electric. A generator ran off the engine so I could plug in electric anywhere.
The motor was almost like new. This van spent it's days parked running power tools.
I stripped it almost to bare metal, did Bondo & Nitrostan where needed and added several coats of the best paint. The interior was in good shape except for a bit of contact rust patches from tools. That was sanded and te interior painted with a Rustoleum product. NEVER DO THAT!
Rustoleum is a slow drying fish oil base enamel.
The van smelled like fisherman's wharf for 3 weeks.
Four years later I tried to trade in the still great looking van to discover the frame and body were barely attached due to rust. This came from lower body panels I addressed by drilling holes and squirting in gutter mender to seal off any rust in the wells.
Look for your truck where ice isn't treated with salt. Portland won't use salt so cars are less rusty. The crap they do use is useless but it makes them feel better.