nope, you're more likely to smack your crank against the floor and the brakes don't line up.
I forgot abut the crank. I figured that one could go with disk brakes it it had the mounts.
I have been thinking of building a 26" commuter/tourer. I keep my eyes open for a late 80s/early 90s MTB with a steel frame which I recall generally had standard road geometries.