Mine were painted black so I wire brushed them with a flexible drill attachment back in December and sealed them with this stuff called Jet Laq
Jet Laq 1200 Non Paint Laquer (250ml) RG75
Still look OK despite the UK winter and salty roads. I'm going to try some buffing compound when the weather gets better and re-do the exhaust pipes & cats. You should be OK wire brushing them.