I'd wax the area around the hole to prevent epoxy outside the hole from bonding and make it easier to remove. Then fill the hole with chopped strand reinforced, epoxy based paste / putty. Cover the hole with blue masking tape to keep it in place. After it sets, remove the tape, wet sand the area to remove unwanted material outside the repaired hole. Drill a hole for the screw, tap it and then reinstall the screw.
Easiest way to get what you need is to go to your local marine store:
Fisheries Supply1900 N Northlake Way
Seattle, WA 98103
and talk to someone in the resin / fillers / fiberglass section. Explain what you are trying to do and they will point you in the right direction and explain how to do it.
'05 Ram 3500, 4x4, DRW, LB, 6spd man, CTD, PRXB exhaust brake, Roadmaster bar
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