Welcome to the forum. It appears you bought a very nice ride that someone put a lot of care into. My suggestions would be take a lot of photos of it now, before anything might change. This is usually an overlooked task, and years later when many things have been modified or improved it’s disappointing to realize there aren’t any “before” pictures.
Next would be a complete systems check of all the operating features to make sure everything is working correctly, like brakes, steering, wipers, heater, turn signals, etc. If you find you have gremlins in the headlight or turn signal wiring, the first improvement is to add separate ground wires to each of the light buckets. These trucks originally depended on the ground side of the electrical system working its way through sheet metal connections back to the battery. After 40-50 years of use, dirt, and corrosion all sorts of odd problems can crop up.
If you get ambitious enough to tackle major restoration aspects, try to keep the projects small enough to get completed over a weekend. It’s much easier to remain enthusiastic about a truck you can actually drive and enjoy.