I don't have dimensions handy but this pic gives you a general sense of the canopy frame "overlap" on the panel. When closed, the bottom of the frame just covers the 8/32 pan head screws around the top perimeter of the panel....the dimension widens from the top to the sides (guessing 3/4 inch at the top to 1 1/2 inches at the sides.
For reference, the two screens are 10.4 inch HXrs and the radio is a GTN650. Note that the panel itself is a single piece of 1/8 inch thick aluminum rather than the standard 3-section panel from Vans.
Chris Engler, Greene, NY
RV 8 Completed and Flying (N184CE), Showplanes Fastback and Cowl, Superior XP-400; Dual GRT 10.4 HXr
Kitfox 7; Rotax 914, Built and Sold
VAF donation gladly paid through December 2019