Fiberglass M3 fenders bonded to steel fenders, help!

[Nonspec325]

Hey all.

I have a 1986 e30 coupe that the owner before me added M3 front and rear fender flares.

The fronts are all metal so thats not a problem, but the backs are fiberglass that have been mounted someway to the original metal of the car.

I'm guessing they wernt mounted properly because after a few autocrosses I get a long crack where the seam is between the fenders and the body. I'm getting tired of sanding and re-priming because the cracks always come back! How do I fix this once and for all? (Ther than removing the fenders and selling them to someone)

I have heard of a metal/fiberglass epoxy... is this the way to go.

Please dont hate me for having M3 flares on a eta... I bought it that way. I'm just trying to make it work. :o

[Naplm00]

clean and prep the innner mating surfaces than use 3M or SEM patch panel bonder

you will need to buy a special $60 caulking gun and a 40 dollar cartridge but, it will never come off

[E30QC]

I don't mind the combo that much, better then a none db equipped fake, this way is like hommage to the m3 while retaining the german autobahn storming muscle car look... that just me though..

[aintnothang]

Pics?