The problem I created here comes from how I drilled the forward canopy sides. The canopy sides lay on top of the aluminum canopy side rail. Holes must be drilled through the plastic canopy and then through the aluminum side rail underneath. With the plastic canopy in place, I used a Plexiglass drill to go through the plastic. When the tip of the Plexiglass drill hit the aluminum behind the plastic, I then finished the hole with a metal cutting drill bit. The problem is that only the point of the Plexi drill was all the way through the plastic. Since the point on the drill is very long, the plastic was not drilled all the way through with the full diameter of the Plexi bit. I was aware of this at the time, but reasoned that the small amount of remaining plastic that the metal cutting bit would now go through would not cause a problem - I was wrong!

After the job was done, I noticed that several of the holes along the canopy side have minute spider fractures around the base of the holes. Although they had not turned into cracks through the entire thickness of the canopy, they were the start of potential cracks. The real problem started after countersinking three holes along each side to temporarily screw the canopy to the side rail and installing #6 screws through the canopy. The stress of the tightened screws was enough to turn one of the spider cracks into a real crack, all the way through the Plexiglass and about 3/4" long. I am fortunate that the crack is not all that long and can be stop drilled and will be concealed by the side skirt. But I will have to be very carefull around the other holes that exhibit the small spider cracks. On the holes that have spide cracks, I am going to counter sink the back side of the hole (as well as the front) in an effort to cut out the spider cracks before they turn into a real crack.

Don't let this happen to you.
This could have easily been prevented by making sure the Plexiglass drill bit went all the way through the plastic with its full diameter before switching to the metal cutting bit. A small shim could be pushed under the canopy to separate the plastic from the aluminum to give the Plexi bit room to go all the way through. In general, I have found the canopy easy to work with. Like anything, a little caution and carefullness goes a long way toward achieving a successful result.