I have attached a number of canopy's the same way you do. Draw the outline of the canopy then pin holes on the inside of the line. That trick works very well, I have had to cut the covering off the plane after a crash to get my canopy off for re-use. My Kaos was pushing 20 years old, that was the fourth covering job after R&R. It's dead now!! I'm building the Bridi Dirty Birdy to replace it. I'm a big Bridi fan and the Kaos has always been a number one plane in my life. I still have a 120 size in my shop. I think I have flown them in every size and they all fly the same, your 40 is the same as my 120, just a bit faster in the roll rate. At the end of any bad day you must fly your Kaos last thing before you go home, it will just make you feel better about yourself!!