[Marvin/TN]

I would get rid of all the old body filler. It will eventually fail anyway if it hasn't already. If you remove the old filler you may be able to do better metal work on the fender and use less filler. Make sure there is no rust under the filler and remember body filler isn't water proof so if it gets wet it the water will go all the down to the metal and rust will form under it and if that happens it will eventually fail. To verify my statement, I started doing collision repair way back in June 1966 and had my own shop until I retired in 1978.