So far the only items of note I've put on top of my X are a new queen mattress and box spring and my spare. The mattress set is moot here, and I put my spare directly on the roof between the crossbars (on top of the Nissan rubber strips you can buy for $18) and it suits me fine. Most anything else will be fine the same way, and if it's not "flat" I can just get a piece of plywood to rest on the rubber strips and then stack from there.

The interior setup might be handy though,
Brent
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