Nice video, thanx for sharing. Personally, I do it a little differently. Since you added the glass from the back, I would bevel the back side, too. This eliminates the crud on the old glass and provides a better bonding surface, Once dry, I rough sand the top, then I will add a layer or two to the top, especially where you've already beveled it, to build that surface back to where it needs to be. I try to minimize the filler where possible. Very cool project...
Good job dude I got a large fiberglass stock tank that my cows stomped a hole in the bottom of this helped a lot to get it repaired a new one is over a grand I was able to fix for under a hundred bucks good as new now if it’ll cool off so cows don’t want to swim in the tank