Guess there's 101 ways to do many things. First, you don't need to cut at the top, you could cut a couple inches above the side windows, this allows the top to be more ridged having more of the walls in place. You'll need to stiffen up the walls, various materials mentioned, I'd use wood stingers like 1x2's use 3M adhesive, that stuff is stronger than the wood or fiberglass.
Think about how the canvas will fold inside to close it. You can use 3 or 4 "loops" of material, like a belt with one end fixed to the top and the other to the side (back and front). When the top is up, these will be tightly stretched up inside the canvas walls, it will help support the canvas walls in higher wind keeping the canvas from forming a pocket of wind (like a sail) stressing the corner attachments at the top and top of the wall. As you lower it, these straps guide the canvas to fold or bunch up keeping the canvas up along the ceiling instead of hanging down inside.
If you're going to have a ceiling light, run your wiring through a rubber tube, like shrink wrap and cover that with the material used as a strap, finish off as you like.
I'd build some small storage pockets or rack along the lower walls at the corners and between windows, this rack frame serves to support the wall.
You'll want to get inside without the top up, those straps will keep the canvas from hanging down so low that you cover a window or your wall storage or just be hanging hitting you in the face if the top isn't up.
Bungee cords might make good straps too.
You'll want your top bolted down, various clamps would work, another reason I'm using wood framing is to attach material and clamps to it.
Lifting shouldn't be hard, it won't have that much weight unless you have a rack and stuff on the top. I'd just unlatch the top and lift one end the brace it, then do the other end. You can lower one end at a time and position the top as you latch it in place. No fancy lifting mech needed.
Aluminum tubing bent in a U (with squarer corners) pivots at the end of the tubing on each side, simply raise the brace front and rear and snap into place on the top. I use to raise a camper top like that when I was 12 years old, it's not that heavy, put your back into it and place the supports in. Takes seconds.
Keeping more of the wall in place will keep the top stronger. I'd go to an auto trim shop and look at the trim/gasket materials they have for the edges, not just foam seals, but hard rubber, glue in place.
One of my projects is similar to yours it's a pickup topper that will lift at the back end with canvas walls.
On the outside of the canvas walls, use about 4-5 inches as a rain flap attached high enough on the outer walls so you can pull in the walls with the rain flap inside to lower the top. Such walls can be packed wet, but you need to dry them out at the first opportunity, but I'm sure you know that.
If I were doing this I'd go for stand up head room. All the best....
Think about how the canvas will fold inside to close it. You can use 3 or 4 "loops" of material, like a belt with one end fixed to the top and the other to the side (back and front). When the top is up, these will be tightly stretched up inside the canvas walls, it will help support the canvas walls in higher wind keeping the canvas from forming a pocket of wind (like a sail) stressing the corner attachments at the top and top of the wall. As you lower it, these straps guide the canvas to fold or bunch up keeping the canvas up along the ceiling instead of hanging down inside.
If you're going to have a ceiling light, run your wiring through a rubber tube, like shrink wrap and cover that with the material used as a strap, finish off as you like.
I'd build some small storage pockets or rack along the lower walls at the corners and between windows, this rack frame serves to support the wall.
You'll want to get inside without the top up, those straps will keep the canvas from hanging down so low that you cover a window or your wall storage or just be hanging hitting you in the face if the top isn't up.
Bungee cords might make good straps too.
You'll want your top bolted down, various clamps would work, another reason I'm using wood framing is to attach material and clamps to it.
Lifting shouldn't be hard, it won't have that much weight unless you have a rack and stuff on the top. I'd just unlatch the top and lift one end the brace it, then do the other end. You can lower one end at a time and position the top as you latch it in place. No fancy lifting mech needed.
Aluminum tubing bent in a U (with squarer corners) pivots at the end of the tubing on each side, simply raise the brace front and rear and snap into place on the top. I use to raise a camper top like that when I was 12 years old, it's not that heavy, put your back into it and place the supports in. Takes seconds.
Keeping more of the wall in place will keep the top stronger. I'd go to an auto trim shop and look at the trim/gasket materials they have for the edges, not just foam seals, but hard rubber, glue in place.
One of my projects is similar to yours it's a pickup topper that will lift at the back end with canvas walls.
On the outside of the canvas walls, use about 4-5 inches as a rain flap attached high enough on the outer walls so you can pull in the walls with the rain flap inside to lower the top. Such walls can be packed wet, but you need to dry them out at the first opportunity, but I'm sure you know that.
If I were doing this I'd go for stand up head room. All the best....