I have some old truck fenders that are pretty rough. Any normal person would have just got new ones. Instead I spent hours welding in patch panels and got the dents tapped out. To look really good they are going to need a skim coat of body filler. My ideas is to use a V notch trowel to put the first coat of filler on. Sand down the top of the vees until the overall profile is correct. This would make sanding easier and also allow me to better judge the depth of filler. Once the profile is correct fill in all of the vee bottoms and then final sand. I would use different color fillers for the vees and the final coat so I don't over sand the final coat of filler. Do any of you auto body guys see an issue with this? Thanks for the help.