It's that time of year so I thought this might be a timely and helpful post.
There are different ways to tackle this problem so let's see 'em.
Here's mine. The only special parts are two winch pulleys I got from Amazon. They each have a 400 lb limit and providedthef extra power to lift the top.
The rest is a 2x4 attached to the ceiling joists with 4 six inch lag bolts, a bunch of eye screws, some chain, another 2x4 that sits above the top and gets lifted and three ratchet straps. The back ratchet strap keeps the top stable from wind and otherwise the top would be tipping up in the front because I didn't center the bottom 2x4.
This required 2 people but could be done with one if I had attached a rope cleat to the wall. I was in a hurry so my wife held the rope while I clipped the chains to the bottom 2x4.
Most likely sent from the crapper