I think these sorts of conversions are very feasible and worthwhile. If you like riding that particular frame and to not want to mess with adapting to a different one, this conversion should just make a known good bike into a surprisingly better one. You should have the frames cold-set to accept a 130 wheel. It might also be good to have the headset bearings overhauled in case there has been a lot of bad weather riding. I'd do the headset and the cold-setting because as you're out on the road, many little problems can make you want to r/r the rear wheel. If that and any other service motions are easy, it will all be more pleasant. The headset is just because you will be away from town for a while, and to start with a dependable machine gives peace of mind, and you will be better prepared. I had cold setting done in Denver (west suburbs area) at Schwab Cycles a number of years ago, and it was perfectly done. There's also Turin Bicycle Coop, but those both are companies that have a lot of experience. I believe Denver has a touring club, or perhaps its called Rocky Mountain Bicycle Touring Club.
I find Campagnolo 3 x 10 to be very reliable and robust, but I would not say that Shimano or even Microshift systems will not go the distance. A shop in Boulder, Vecchio's, is one of the best experts in Campy, anywhere in the USA. If they tell you it's a bad idea, it's a bad idea.
I would go 3x10, Shimano or Campy. I would try to set up a 50/40/30 chainset, with the widest cassette the derailleurs can handle. I think it's more important to have the lowest possible low gears than the highest high., though I would want to have a top in the 95 to 110 range. But also good brakes since I would imagine screaming down mountains from time to time. Off the shelf I'd look for 12/36. If you can only handle that with Shimano, then make the rest of the system Shimano. I would not play games with mixing shifter system brands (like Shimergnolo or such). For nearly all Campy systems, you can mix levels, unlike some Shimano (I'm not very experienced with Shimano, but I've learned to trust Campagnolo). One selection criterion is, for which system do you have confidence in managing on-road maintenance or adjustments?
You will need a 130 mm 10 or more speed hub depending how you set things up. If you are good with wheels and spokes, I'd build a new hub into the existing rim, if it is not toast.
As far as saddle, pedals, seatpost, stem and handlebars, I think it's all very dependent on taste and habit.
Last edited by Road Fan; 12-30-20 at 11:46 AM.