it would be a lot easier if you had a good compression test; that would tell you if the rings are OK.
OTOH, if you can do an engine assembly yourself, I'd just pull the engine and do a complete overhaul - rings, bearings, sleeves, new rod bolts, new crank cap nuts, etc. It really isn't that hard, and you won't have to wonder "what was done previously". Parts are not all that expensive, and your labor would be "free".
And a few long term issues - clutch disc for example, oil pump overhaul (Just send it to Gordon Raymond, a BB member and master of oil pumps and weber carbs). Check crank aluminum plugs, consider drilling the #2 and #4 bearing oil galleries as well.
Then redo the seat cushions and upholstery, and the carpets, and .....
It's always easy to get lost in the "Oh, while I'm there I'll just add...". ;-)