So... After holding my VN750 front fender up to the VN900 CUSTOM fender.
I'd have to say that getting it to work would be a MAYBE
It will not mount straight up, you would have to fabricate a set of mounts similar to the ones on the custom.
Also, you have to keep in mind that the VN700/750 only has a 100mm wide stock tire. While people commonly push it out to a 110mm tire, that's still significantly narrower then the stock 150mm tire on the VN900 classic.
If you're playing around with the idea of different wheels as well, the modification might be feasible, but In my mind, it's something that would be better suited to the custom model due to the narrower wheel.