Belt grinder advices

[rendoman]

Just finished the polishing attachment.
The belt run strainght with no trouble, the shaft for cotton wheel is 15mm with 20mm bushing, left threaded.

Now I have to buy wheels and pastes. Have you any advice?
I only have White paste, I think I need one wheel for each color of paste, right?
I want to polish aluminum and brass.
I think I need : light blue, pink and brown. There is also a green for stainless, but I don't know if it can be good as last passage before brown

DISCO RUOTA in COTONE CUCITO TRAPUNTATO per LUCIDATURA di ACCIAIO INOX OTTONE

PASTA ABRASIVA : LUCIDATURA A SPECCHIO METALLI ACCIAIO INOX OTTONE | eBay