I ended up ordering a hoist from hoistlifts.com. It is suitable for both TJ and JK 2 door jeeps. It turned up about 5 days later (from the USA) in a tiny box:
Contents of tiny box:
Lifting it off:
Hanging free:
A few things to note:
1) The straps are easy enough to guide inside the jeep, but the instructions are very generic and do not explain how to use the straps thoroughly - i had to figure it out. The diagram shows some sort of hardtop for a sports car and mentions rear clips - the jeep version doesn't have rear clips but i had to figure this out.
2) It takes a little bit of adjusting to get the centre balance point, but not hard. Lift the top an inch, see how it hangs, lower and adjust and repeat as necessary. You need a high ceiling, about 1-2 feet at least of clearance above the height of the hardtop when it's sitting on the jeep.
3) The supplied hand brake (rated 600lbs) winch seems a bit finicky. It has a lever which appears to have 3 positions - 1) winch in 2) winch out 3) no brake. I had a bit of a test, it was noisy and i just didn't trust the 3 position lever on the hand winch. No mention of these lever positions in the instructions. It just so happens i had another hand winch to compare with - I bought a Rock hand brake winch (rated 1200lbs) from ebay about a year or so ago when i started thinking about a hoist. I ended up using the mounting bracket from this hoist kit but using the Rock hand winch. The Rock hand winch has no levers or clutch etc, you just wind it up and wind it down and let it go and it just holds the load. I'm sure the supplied winch works well, but the rock winch works better, though it would increase the cost price. See the below pic for the winch comparison. Rock winch on the right, supplied winch on left. Also note the warning sticker on the supplied winch states "Not for lifting Humans" so that was also a deal breaker
It works well and i can easily remove and re-install the top by myself without any dramas.
cheers