A hitch hanging from a pin box is a static load. When it's bouncing down the road it's a dynamic load. The design factor for a static load is generally X1 and for a dynamic load is generally X10, so theoretically you can hang it on the pin with no issue. Having said that I don't think I would do it. It just doesn't seem right to have that thing dangling there.
My B&W slider weighs 275# and even with the top removed it's still over 200.
I bought an engine lift from Harbor Freight on sale for $99 and made a lift adaptor for about $10 like E-trailer sells for $50. Just used a 2"x6" pipe nipple with two end caps. Drilled and tapped one cap for an eye bolt. Works like a charm. I had to make an extension for the lift to reach far enough into the truck bed but it is a 1 ton lift so not an issue .
Should have seen the look on the face of the cashier when I checked out of the hardware store with the pipe. Hmmm, Pipe bomb?
Anyway I pull it for off season and set it on a furniture dolly and roll it to a corner of the garage for storage.
This works for me.
Hardest part is on reinstallation getting those darn pucks to line up with the holes cleanly. Haven't done it yet. I just set it in and jockey each corner with a short pinch bar to get it to drop in.