Reddit mentions of Honda 100-350cc OHC Singles, 1969-1982; Service, Repair, Maintenance (Clymer Motorcycle Repair Series, M315)

If you haven't already, get the Clymer manual. I can't seem to find a Honda Service Manual, so this one will probably have to do.

Bike Bandit seems to have a good availability of parts for your carb. The gasket set looks cheap, as that's the most likely thing that'll need replacing first. Give the whole assembly a good cleaning and inspection.

Check for cracks and tolerances in both brakes and the chain, any looseness in the steering and wheel bearings, and pitting on the travel area of the fork tubes. Put some new fork oil in if the seals are ok (probably not, but who knows?).

Check for corrosion on electrical contacts (especially grounds) and sand them clean as required. Use dielectric grease to prevent future corrosion.

There is a much bigger list of possibilities, but that's part of the fun of owning an older bike. You get to know it like the back of your hand and will feel ever so satisfied when you fix something and it actually works. The more complex the bike, the more rare this is in my situation.

Just get it running and stopping properly and ride the shit out of it, you stupid lucky bastard.