i used evercoat light weight filler its around 25.00 a gallon
i also bought a small can of bondo gold its their so called premium
filler with the red hardener its hard to tell when its mixed well.
the evercoat is white and the hardener i used is blue worked great
for me. if you are a newbe like me on filler work get a bunch
as most of it will end up on the floor.