It would be easy to come up from a cross bar, through the hub opening with a plate/nut of some sort to tighten down.
I would reconsider roof mounting personally if you can though. That's a tall lift for a (possibly) heavy, awkward round object. Not to mention if you're changing on the trail it's gonna be covered in mud. Then that weight is right at the very highest point of the truck. There are some cheaper alternate hitch mounting options out there, without having a full bumper/swingout.
Just my .02
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2007 4Runner Limited V8
| 2.5 Fox 3" lift w/ remotes & DSC | Dobinson 677V rear | SPC UCAs | 1" BL | SCS F5 | 315/70 DuraTracs | Prinsu full rack | RLC rear bumper/swingout | C4 front bumper | Warn VR8-S | F55 fairlead/Flatlink-E | Rocksteady skids | ARB 2500 awning | Dometic CFX 40W | Partner Steel 22" stove | Adventure Index drawer/sleeping platform | ARB twin compressor | Odyssey 34R dual batteries | Blue Sea SI ACR/fuse panel/USB | Renogy 100W Eclipse | Baja Designs Squadron R & S2 | G5R retrofits | Doug Thorley headers/Y pipe | weBoost OTR |