Touring bike conversion
Hello everyone, I've done some searching before posting but just looking for some quick hits for guidance. I'm looking to build up a late 60s touring frame to a something that can take on a bit of fire-roading/bike camping but still mostly iffy pavement. For going places my road bike won't and well, I like keeping my MTBs on singletrack. Anyway, the frame came with 27/1.25 tires but there is PLENTY of room. I'm leaning toward going 700x38 (I have a couple spare 700 wheel sets). General recs for tires and gearing? I'll be using friction shifters so I have some freedom as to cobbling together spec. Thank you for any help.