PeterK said:
Another advantage of the overhead hoist is that you can gently set the top back on the car by yourself.
When I built the prototype, a hoist system was not feasible. So far in all of my garages, the space over the car has to be kept clear for the garage door. Even if the ceiling was high enough to clear a hardtop in a sling above an open garage door, the garage door track was in the way. Sometimes you have no choice but to put removable hardtop on a rack to store off to the side.
When I was selling my hardtop, people on the 6-Pack site saw the rack and wanted the plans for how I built it. I had to go out with a pad, paper and tape measure to draw up the plans. It was built with left over lumber from other projects, there was never an official set of plans, I just built it as I went with a couple of quick measurements. The only pieces that I went out and purchased were the casters. After it was built, I could have modified it but there was no need, it did its job very well. Along with the hardtop, my rack held a couple of sets of fender covers, some towels, extension cords and trouble lights.
The rack could have been built much less substantially if I had only planned on holding the hard top itself on it. Keeping the footprint in mind, I made sure it did more than just hold the hardtop. I was able to store items below it and on other parts of the rack as well. Plus the casters allowed it to be easily repositioned whenever I needed to for cleaning, rearranging etc... That rack design was built solely for my intended purposes. I was flattered and a little surprised when so many people on the 6-Pack list wanted copies of the design so they could build something similar to hold their own hard tops. That prototype rack still lives, it is now holding a hard top for a TR3, with no modifications to be able to do so.