I would think that the "top" of my tray is the end that I insert first into the printer, but the AudioLabel template for my new Canon MG6220 has about 3.5 inches from the top edge to the edge of the CD, whereas the distance on my tray (tray "G") appears to be about 1.5 inches.
What I would consider the "bottom" end of the tray does indeed have about 3.5 inches from the edge of the tray to the edge of the disc.
Further, Canon's trays are numbered E, F, G and cross many different models... my new tray is # G... any particular reason AudioLabel doesn't use these same identifiers, either in place of or in addition to the printer model number?