I agree pertol/gasoline does work very well ...but it is dangerous if you smoke and it does bad things to your hands ..it dries them out causing the skin to split...no more polishing for a while....in the UK there is a product called 'star drops' don't know if you have it 'over there' but it works wonders used neat on grubby chrome and especially on alloy compnents even usefull on painted grubby frames if diluted 20-1.
steve chambers
chesterfield
england