Filling Holes in Fiberglass Trunk Deck ?

[dmc_racing]

I need to fill 4 holes on a fiberglass trunk deck. These are the original mounting holes for a spoiler / wing on a 04 Mustang. What would be best to use to fill these holes with minimal shrinkage? Also what would you use on the underside for something to adhere to. I'm wanting it to look as clean as possible on the underside. :confused:

[BBRam]

I would grind both sides, mix Duraglas body filler with some resin and strands of fiberglass cloth, spread both side's and finish.

[Rocketron]

duraglass shrinks to much and has no strenght what so ever i recomend ECONO FILL it can be picked up at any fiberglass product store or marine store it comes in a powder form and is NOT micro balloons you mix some resin in with it till you get a paste with a satified thickness add hardner, then using aluminum tape on one side of the trunk fill the hole with the paste and sand you get no shrinkage
and strenght too make sure you spread the paste so you can no longer see the hole. then sand and add a little filler and sand again and prime

duraglass/kitty hair Will shrink under heat