It's a 40-yr history, Bought the bike at school in Nashville, and left the shop with an Unicanitor saddle. In '78, the original splined SR crank ('77 model GP) stripped out climbing the hill a block from home in Austin. First rebuild was around a Sugino Mighty Comp and Zeus/Rigida wheelset. A great benefit was all the workers at the UT Co-op bike shop raced, won parts and sold them cheap in the shop. With the new wheels, narrowed the freewheel, and switched to Shimano 600 derailleurs.
(this is the 90s saddle)

10 years ago in Bulverde, went to the moustache cockpit, Ultra 6 in the rear with half steps on the crank - great in rolling hills, but still torture to make the final climb home.

By then I had 25,000 mi on the wheelset. Got a great deal on an unused Phil/Synergy 700c freewheel wheelset that a guy had built for an 80s touring bike project, but sold out the project to do something different - it was a great opportunity.
The rebuild around that cold-set the rear triangles to 126mm, wide-7 rear, found a NOS Cyclone GT RD, still the 600 FD (Great FD!);
the cyclotouriste crank is Sun XCD with a TA triple stack, 46/42/26T half-steps plus granny (shopped in Japan for the crank arms, and Germany for the rings);
SKF 121mm BB with 2.5mm spacer for offset, and added Honjo fenders.
My BB shell is British thread (ISO) and I believe yours will be, as well (you'll need to rebuild the BB anyway, so check it out then and decide if you want something new)

The granny lets me approach in a 50" gear, then shift down and up as the grade on the final climb home waxes and wanes. There are a few spots on the climb home where the grade is 14%. Here's the gear analysis.
It's an evolution - not the kind of thing you'd do from scratch...new bike? improve an old friend? It's about the same, but a little bit at a time feels better.
Plus, as we all know here, working on bikes is tinkertoys for grownups

I also sold these pedals - they were too wide for the low Raleigh BB and were terrible about strikes - I now have narrow Blackspire El gordo pedals in blue, and they have excellent clearance - I can power through turns.
The Sugino Mighty Comp crank ended up on my daughter's project Team Fuji the summer after I finished this.