fiberglass over an oem enclosure

i just bought a 2009 ford focus ses it has an 8" factory sub in the trunk but i want to beef it up. i would like to keep the oem location. the oem enclosure is made out of moulded plastic or composite material. i have removed it checked for size, and the volume is sufficient for the 8 i have. i would like to fiberglass over the top of this enclosure to make it more rigid. just wondering if i will have any issues bonding the fiberglass to the plastic enclosure, or anything else i am forgetting. just seems it would save me more time than building a whole new enclosure, but just the plastic alone would probably flex and boom alot with a real sub in it with some real wattage. any help is appreciated

If your going to be using the OEM plastic, you must sand it down ( 80 grit ) and also drill in small holes into the plastic so that the fiberglass has something to bite into and hold. Otherwise the fiberglass will eventually separate from the plastic.Jeff

Velocity Custom Home Theater

Mobile Audio/Video Specialist

Morden, Manitoba CANADA

You can also read my post about how to make oem panels look like fiberglass without all the work .The title to the post is look-a-like fiberglass-A vision without a plan is just a hallucination-

you shouldnt need to fiberglass reinforce the the sub enclosure most fords were built with fairly high quality bose sound systems, i dont know what you intend on replacing it with but i would be careful your not actually downgrading it. ive done a number of swaps of boston acoustic subs into fords and they were fine stock mounts.