i used my grinder with a wire brush the did the trick for me only other thing i did wrong was let it dry the put it back on started the quad smelled it curing thought well that should be good enough... hit the woods and the paint completely dried with spots of mud here and there... shiz wolnt even wash off so when you do it let it cure completely
if i was you orange and silver sound beast i would do it like this if you have all the parts
silancer = orange with a silver cap on the front
header= silver
heat shield = orange