The normal way to remove a completed sliding canopy from a side-by-side RV is to remove the bolts that attach the WD-644 canopy rollers to the slider frame, then lift the frame up off the rails. I realized that if I could make it relatively easy to remove the rear anchor pin blocks (which also function as the aft canopy stops) it would then be a cinch to instead slide the canopy straight back until the rollers slid out of the side rails. By removing the canopy that way, you avoid tearing up the paint on the roller weldments, and you don't have to mess around with trying to get a wrench on the nut that attaches the roller to the frame.
The challenge, though, is that the design of the rear anchor block mounting bracket prevents you from removing it from the fuselage unless the canopy is removed first. You have to start by removing the screws that capture the plastic block within the U-shaped bracket, so that you can remove the block and get access to the bolts that hold the bracket to to the fuselage longeron. But of course, you can't get at the screws in the first place, because the canopy side skirts are in the way.
So, my bright idea was to modify the C-677 rear pin anchor block mounting brackets by riveting some MS21051-L3 nutplates inside:
Now instead of using bolts through the top of the brackets and nuts on the underside of the longeron, the bolts come up from underneath:
To provide clearance for the nutplates and bolt threads, I drilled very slightly into the plastic anchor block: (hard to see in this photo)
Now I can remove the entire anchor block/bracket assembly from inside the fuselage, then slide the canopy backwards off the rails until it can be lifted straight up and stored safely. Hopefully this will prove to be a useful modification down the road. I will mark the bolt heads with inspection lacquer and check them periodically, although they are plenty snug in the nutplates right now.