I was lazy and just painted Sash & Sabre frock coat guys with white pants (yes, I know, that's only for summer on ship. Whatever. They're also walking around with steampowered clanks). The other thing to watch out for is the rank on the NCOs; the chevrons go the other way on marines, so if you want to be a stickler for detail, you should probably shave them off and paint them on the 'correct' direction.
Again, that is if you're not lazy like me.
