Will this fit a four-door DeSoto Custom?

No. It is listed for two-door models only, and it is the right-hand outer panel. Four-door cars use a longer rocker and need a different part.

Is this the whole rocker or just the outer skin?

It is an outer rocker repair section. The inner rocker, floor edge and structural pieces are not included, so inspect those before you cut.

It is made from 19-gauge steel, which is heavier than the thin stock used in many generic patch panels and holds its shape better during welding.

No. It is bare steel, so clean it, apply a weld-through or epoxy primer, and finish it with paint and cavity protection after installation.

Only if you can cut, shape and weld sheet steel. The panel needs trimming to fit and butt or lap welding along the sill, plus seam sealing and paint.

This is the right-hand side, the passenger side on US-market left-hand-drive cars. Check which sill is rusted before ordering.

At Classic 2 Current Fabrication, for $65.99, as of our latest check.

2 stores we checked sell it, including Classic 2 Current Fabrication, Amazon.

$65.99at Classic 2 Current FabricationChecked Nov 12

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