I decided to go exploring some of the lumps and bumps in the bodywork of the project car and found this. Look how thick the filler is.

Hope there's not too much more in other places!

Nigel:

Although it looks as though that body filler is thick, it probably isn't over 3/16" thick. The reason it looks thick is that you've ground it off at an angle.

When they brazed that reinforcing plate they tapped in the edges to try to hide the braze.

This is hard to do in the first place, and not unusual to tap the edges down. The hard part to do is to blend the repair into the panel all the way up.

More than likely they long boarded the sanding and that ended up taking the filler way up high and low. In essence they ended up "chasing" the dent. Can't explain this briefly, but it is a common body working problem. The problem lies in NOT sanding down far enough and then adding more body filler to try to smooth out the new "high" you perceive is there.

Add to it that the roof / fender body seam is there and it is even easier to get into chasing the finish.

2¢