Grant,
We just went through the same thing last month. We were so overwhelmed with boxes in the 5th wheel that we rented a 5x5 storage locker and put most of them in it. Then we started bringing a few boxes at a time back and getting organized. That worked much better than moving the same things fifty zillion times. We just emptied the last box yesterday and it was a great feeling of accomplishment
We do have two pods in permanent storage but they're only 5x7x8 and not nearly as expensive as storage lockers. Plus, they're more secure and stored inside a warehouse.
If you can't open your slides, I'd say you're going to have a tough time
Good luck!
Judy