I just did my canopy and i have to say, It went very smooth with the screws. As long as you use a dull drill bit you will have no problems with drilling the canopy. One thing to consider before using sicaflex is what do you do with the pre drilled holes in the skins. I assume you just let the glue ooze out of the holes and grind it down after it dries. However i cant imagine the glue staying inside a #30 hole in a .025" thick skin. In a couple years i would expect it to crack and fall out. I have dealt with some good glues designed for use on aluminum but none of them are that good.