I managed to obtain 2 steel rear fenders ("mudguards" in Australia) that needed a fair bit of repair work. I will show some of that soon but one of the few body mods I am making is to "bob" the rear fenders.
I don't know where this term comes from but it means to shorten them at the rear. Maybe like bobbing a dogs tail? When an A model is rodded, it results in the car being much lower than Henry originally envisaged it and the rear fenders almost seem to be scraping on the ground, hence the 'bobbing" by various amounts. I elected to remove 4" (100mm) from mine. Not too drastic as I'm basically not modifying the body otherwise.
I cut a strip of steel 4" wide and placed it across the area to be removed and scribed both sides onto the fenders for the cut lines. This section was removed using a jig saw then trimmed up carefully with tin snips.
At the moment, Ii have only tack welded the pieces back together, but you can see the effect already.
This particular fender was badly damaged in this area when I got it, so needs a bit of panel beating also.
A cut was made on the lower section, at left, to allow this section to mate up correctly with the upper piece. This is because the fender tapers down in this area. A long triangular piece of steel will be welded into this area and shaped as required.