Needed a way to get 53 storage bins weighing about 80 lbs each 12 feet off the floor.
This was born.
Four of the garage door pulleys are bolted through one piece of hardwood plywood and interface with the edge rail of the extension ladder. The holes are drilled such that the pulleys can not be removed from the ladder without completely removing the bolt for a little bit of safety.
The remaining pulley is at the top of the ladder, bolted through a piece of bed rail (hardened angle iron) with notches cut into it to fit the extension ladder slide brackets.
An ATV winch and battery are mounted below the lifting platform.
Two shelf brackets with some more hardwood plywood screwed on, and two small sections of shelf rail screwed to the pulley plywood finish out the hack.
Way more than adequate torque from the winch. A single run of cable would have worked as well and doubled the lift speed, but the winch had to be mounted off center to fit between the bottom rails. This lended itself to using a pulley at the top so the resulting lifting force goes straight up the ladder and the plywood pulleys just keep it from tipping.
I've lifted over 200lbs quite easily with this setup, but I wouldn't recommend it as it will strain the rivets which are supporting the upper pulley. It's also a little hard to safely get that much weight off the ladder at the top.