Trad - are the scuffs on the tank in the side panels or the top? If they are in the top, they can be wet sanded. I've done it numerous times. 1,000 then 2,000 then straight to buffing with an orange foam pad, then to white pad.
Then black side panels are VERY tricky. They are a single stage only (as I suspect you realize). You "can" wet sand them, but be very gentle. I'd start at 2,000 grit, sand in opposite direction of the scratches. Then go immediately to buffing with white pad. The buffing will remove some color, so go easy. if the scratch is too deep, it won't come out, but you may be able to knock it back enough to be happy with it.
Of course, a high quality synthetic waxing afterwards is highly recommended. And I always begin wax/buff work with using Denatured Alcohol to wipe down the paint first. Won't hurt it a bit, strips any residue off. Then I clean the paint with a clay bar to remove any remaining surface contaminants that may come loose and scratch deeper.
Here's a pic of a members tank I helped him out with (it was very badly oxidized and wicked scratched). Came out very nicely and he was super stoked.
