The photos below show how I notched a big bumper fender and converted it to a small bumper fender.
I had an early fender to trace out a template from a shoebox

Here is a photo showing the notch on a small bumper fender
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Here is another photo at a different camera angle
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The fender is folded at the bottom of the metal that makes
the headlight assembly |
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| Cardboard template shows where the
metal will be folded...NOT where to cut. Flip the template
over and use the other side for the other fender |
Notice the bottom edge is flush along with the front of
the fender. This will need to be changed before marking the
fender |
Here is the early small bumper fender. Notice the
headlight adjustment screw is on the bottom |
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| Notice the headlight adjustment
screw is on top on most big bumper fenders. The difference
between the metal behind the headlight will make the notch
to big if tracing the template without adjusting for this
difference |
Notice when the template is laid in place...the edge of
the cardboard is about 3/16" -1/4" higher than the headlight
assembly metal |
Slide the template down so the cardboard is even with
the headlight assembly metal |
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| Trace the template on the fender.
This is where the metal will be folded. DO NOT CUT on this
line |
The top lip is about 1" wide |
Measure down 1" from the line you drew with the template |
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| Measure over about 1/2” from the
fold line and draw a line. This is where you will be cutting |
The shaded area is the lip that will be folded |
Big bumper fender is on the bottom. After you notch the
fender the hole close to the front of the fender will be
gone. A new hole will be drilled in the big bumper fender
lip |
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