Norton tank on a CB750?

I'm building a cafe inspired street bike out of an old Honda CB750. Got most of it sorted out but still playing with the tank.

I've got a lead on an a bunch of old alloy norton tanks needing some repair, including a 3 gallon manx style tank, a manx lyta short track tank, and a 4 1/2 gallon classic norton tank. I've only seen pictures, and have no dimension references.

Anyone willing to wager a guess which would fit best over a CB750 frame? Anyone have rough dimensions, or a page where I can check them out? Anyone ever done something similar?


Thanks in advance,

Vin