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Will cutting the fender wells affect structural integrity?

Documented on the Ford Mustang build

Published February 26, 2026

If you remove factory structural seams you can affect rigidity.

Full Answer

If you remove factory structural seams you can affect rigidity. The typical approach is to reinforce the area with welded panels or proper fasteners and seam sealer; doing the job with solid welds and proper metal backing restores strength. If unsure, keep reinforcement pieces and practice proper welding techniques.

Related Parts

Body filler (small tub)
$15
MIG weld wire (flux core/alloy appropriate for mild steel)
$15
Grinding / flap discs (pack)
$10
Mild steel sheet (approx. 18ga)
$60
Aftermarket fender well liners / splash shield (trim-to-fit)
$80
Pop rivets (assortment)
$10
Automotive seam sealer (tube)
$12
Primer / rattle-can (epoxy or etch primer)
$20
Underbody coating / rustproof spray
$18

Related Tools

Jack and jack stands
Angle grinder
MIG welder
Hammer and dolly set
Drill and spot weld cutter
Cutoff wheel / abrasive wheel
Reciprocating saw / Sawzall
C-clamps / locking pliers
Marker / measuring tape / templates