First, don't sand, wire brush or use any abrasives. Some of the plastic parts you are concerned about have a mold release as part of the material as a manufacturing aid, get the part out of the mold. The fiberglass may also have built in mold release. What that may do is assist you in removing the black paint. Paint don't stick to mold release parts well (unless a solvent is used to get rid of the mold release prior to painting). Your goal should also include not adversely affecting the grain on the items. Some of the products I've tried are: Krud Kutter , a paint remover available from Home Depot; Jasco, another paint remover also from Home Depot; Goof Off, this is a LAST resort paint remover. As always, try some on a small spot and if you are not happy with the results, don't go further. Try something else. For tools, a plastic sponge, scrub brush, towels.
Jim