gluing a recoil pad to a fibreglass stock

[lurcher]

I have a Hightech fibreglass stock the butt end is just foam filler (I have only ever worked with one other fibreglass stock and the butt on that was glassed over).The instructions say to just go ahead and epoxy the recoil pad on. I am concerned that if I glue it to the foam it may come adrift if it gets a serious knock? or will it be OK?
Cheers in advance for your advice

 

[shortgrass]

Epoxy in a couple of those 'screw in' dry wall anchors. Then screw and glue the pad on.