Just received a 1980 XLS that needs work. One of the primary repair jobs is replacing the clutch. After removing the primary cover and removing the disks/plates, I discovered that the drum and sprockets are quite rusty (appears to be surface type rust, however it is not just a thin film). The chain and tensioner appear to be ok, as do the teeth on the drives. Should I replace the drum and sprocket, or is it acceptable to just clean them up (wire wheel, non-abrasive blasting, etc.)? Thanks for any advice.