how to attach fiberglass components?

The trunk floor is usually a good mounting spot for the subs. I use 3 bolts to hold down rear corner sub enclosures. If the floor is not accessible or you can not drill a hole into the floor for some reason, mount a MDF board the shape of the bottom of the enclosure and mount this piece to the floor and then mount the enclosure to the MDF.

Along the same line as the original post, i too have been reading a lot and i'm ready to try but it's not obvious how to attach the finish product..for instance:  I plan to build a kickpanel enclosure using my actuall kickpanels (after practicing on a junkyard pair), they are held in place by one screw.  After the enclosure is built, the screw hole will no longer be accessible so i can't re-install them with the same screw. 

If my life depended on figuring-out how to re-install them.....i would be dead!!

Thanks 

I"m not sure what you call them, but they can be found at lowes and HD, but they are similar to your standard mounting brackets that are bolted into place,  at one end is a hole for a screw or bolt, at the other end is a slot to slide over a screw head and then pulled to lock into place

its a pain in the butt, but its the simplest way to do it

another method that works well (altho easy to steal) is using plain old velcro