also keep simple green away from aluminum. It will leave white residue stains on intake maniifolds. Good for empty egine bays. I would dilute 50/50.
another good one is the new 401 super degreaser. its in a purple bottle and contains a high amount of caustic, for over the counter. the caustic type solutions work best on a warm surface, so if you preheat your fenders with a hair dryer (not melting hot, just warm to the touch) it will increase the cutting power of any of those solutions. unlike a bleach solution which will work better on a cold surface and then warm temps neutralize its strength. Just an FYI.
