KR> fasteners

[DAN INA GLANDT]

Hi,  
Is there an accepted or common practice for putting screws into the fiberglass. 
 I need to have several access panels to get to the aileron and flap links on 
the bottom of the wing.  Have thought of things like drill a 1/4 inch or so 
hole through the fiberglass and into the foam.  Enlarge the hole in the foam 
and then fill it with mix of epoxy and something, balloons, flox ?  Then drill 
and tap into this for the screw.  ??
Dan