David,

Miine fits on top of the glare shield at the aft edge, but I extended my glareshield edge to about four inches aft of the instrument panel.  Even there, the XRX "just" fits, so it has a piece of velcro cloth on the corner to protect the canopy.

Since there is such a slope in the canopy at that point, maybe a standard glareshield is just too close.