When I got my Skorpion, the rear can was pretty ratty - the thing was well blued, the joint had been leaking for several hundred years and the bike had been dragged along behind a horse by the looks of the deep scratches along the side. The potential cost of a nice new unit gave the missus a dose of the screaming jeebies in the kitchen (not a pretty sight I'll have you know) so, with nothing to lose, I set to with some decent quality Wet 'n Dry (forget Halfords- crap) and soap, along with some Solvol Autosol.
I started off by hand-burnishing out the scratches with 400 grade on a rubber pad (20 minutes) then smoothed off the resulting smooth-but-rough patches with 600 (10 minutes), finally finishing off all over with 1200 and soap (half an hour). This left me with a matt silver, un-blued, leakage-mark and scratch-free can (plus aching fingers - but a smug grin).
The Solvol Autosol (nothing else I've found will do) and a brisk 15 minute buff on the bench with a piece of Terry Towelling saw the stainless start to glow encouragingly .... see pics here-
A further 15 minutes the following day and I now have a seriously new-looking can that's the equal to the wife's new ER5.

HTH
