i like MAS epoxy but mainly for bonding stuff, i have actually used on holes like that gorilla tape on the hole on one side ans the on the other working side i would lay my wax paper to it so the tape is support and keeps the resin from leaking thru, i always use either gorilla or duc tape on the back side to hold my patch piece in and then i lay my part in place and then fill the voids with resin once dry i take the tape off and then grind to ruff the new resin slightly and then i'll glass both sides heavy to hold my filler patch in place and then line sand smooth and then mix resin with micro balloons and then wipe acoat over my patch to fill any pits or low areas and then line sand straight and smooth to look like it never was fixed.
look at this from my V20 work where i use wood but you are doing the same with glass i filled with a wood piece that i taped the hole up so no leaks and then filled the voids with resin and then glassed both sides sand and microed the area now just need to sand
http://www.wellcraftv20.com/cgi-bin/...45;start=60#60