The following operation steps are shown on model 171.
1 Expose spot welds on side rear inside panel (1) and cut out (area A).
2 Remove side rear inside panel (1).
P63.20-4593-03
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3 Grind mating surfaces down to bare metal in the crosshatched areas.
Grind spot weld flanges down to bare metal on both sides.
4 Remove shavings and drill chips.
5 Coat insides of spot weld flange with zinc dust paint.