Being that the 370 is in the same family as the 429 and 460 engines, you could possibly install a 429 or 460, or maybe just use some heads and intake/exhaust solutions from the 429/460 automotive family.
My brother put a mid-to-late 70's era (brand new crate engine) 429 into his '68 F600 flatbed. Going from the original 330, he said it was a major wake-up in power.
Going from a 370 to a 429 or 460 would be even easier.
Not sure what the differences are between the truck 370/429 vs. car 429/460. Compression ratios, cams, and other internals are different, but not sure about engine mounts and bell housing patterns. Maybe someone can advise.
Ford, and I suppose everyone else, "lo-po's" the truck engines. Compression ratios are in the 7s, cams look round to the naked eye, carbs are small. Thus, you have low end torque and they last a long time.
You have to be careful making a swap. Consider the power curve of a newer engine and how it matches the gearing etc.
A 460 with an rv cam would be fairly cheap, and bring you 50 to 100 lb/ft of extra torque methinks.