Frustrated with inability to do body work!

Ive been working on the front fenders of my 66 dart on and off for 6 weeks. Im no farther ahead tonight then I was at the beginning. Problem Im having isnt making surface smooth but its creating or should I say recreating the body lines. Heres the history, My dart is a 270, it had a body trim that went from front to rear about 3/4 of the way towards the top of the fenders and door and rear quarters. Ive removed them and will not be using them again so I had to weld the holes that are in the body to hold trim in place. Here is a pic of the fender.
View attachment 1715083199
Above the center between the 2 indents are the biggest issue. There are 3 places that you can see I have put filler into. My issue is remaking that body line both top and bottom. First I am struggling to find the exact line to follow. Ive been trying to stretch tape along the old line but its very hard to see that exact line since the line is rounded toward the indents. I can make the indented area flat but im struggling to then match the rounded body line to the flat area without going to high into the center area or to low into the flat indented area. I feel like all i do is make filler and sand it off and repeat! I tried using 180 grit and also 80 grit on sanding blocks both flat and rounded ones.
View attachment 1715083200 Above you can see I have it somewhat filled in but it was to low at the flat area of the indent. Below it looks like I have body lines but they werent straight. Any suggestions on a good method would be greatly appreciated.
View attachment 1715083201
I want to do this myself and not have to pay someone to do it but so far I am going nowhere fast!
Thanks Rod
Mine looked similar to yours (worse than yours by a lot.) I used 3/4 pvc on the inside curved areas of the front side of the fenders for the inner outward curved parts I used a slightly concave sanded 2x4 the width of the smallest area, the fender lip areas I used 1 and 1-1/4 pvc wraped in sandpaper to help define shape. for the body lines to stay sharp, straight and crisp I taped one side and sanded up to that line then taped the other side and did the same sand up to. that kept the body lines sharp
https://video.search.yahoo.com/yhs/...=1240d205b5d56a11e3fc050dbd74abd8&action=view
If you have a good opposite fender or curved section you could "cheat" by placing or taping a piece of saran wrap onto the curved section you want to duplicate cutting a 1"x 2" the height of the curved section and then slather a bit of body filler on the saran wrap to shape it. stick the 1"x2" onto the body filler before it hardens and you now have a custom shaped sanding block. peel saran wrap off of bondo(if you can) add stick on sandpaper and go to town on the curved surface.
https://video.search.yahoo.com/yhs/...=51deebd2e3c73f203cd338b73a4e2b23&action=view

the beginning
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mostly fixed not metal worked yet to finish welds and shape
!metal front fender repair.jpg


Stud guns are your friend!
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that darn dent by the front bumper is finally gone.

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and done
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the defining lines on the 66 is a hard part to get right. mine was in the bumper recess area(dented in @ pic #2 and the top body line that someone had dented down midway in the body line with what looked to be a rounded ballpeen hammer ) I spent 3 weeks getting rid of a slight curve on the rear section of the rear lower patch panel and then realized that it was supposed to be in there! took 3 solid days of metal stretching to get it back in @$#%%$ DUH moment.