DWG 44 calls for a gap at the aft end of the frame to the canopy rail of 5/8" to 3/4" mine was 2 3/4"!
I checked VAF and this is not uncommon. Gunter Malich gave the tip of standing on the frame using some 4 x 2 as a pivot point - it worked a treat (forgive the weight lifters belt but my back is not the strongest in the world and initilally it took quite a bit of grunt!).
I settled for 5/8" after reading a thread about fitting the skirt.
