Ob- I'd go with something called 660 Quick metal. It's made for keyed assys similar to this sort of application.
Clean and degrease all surfaces, draw a bead into the key slot, fit the key, and smear a bead across the contact area of the OD of the shaft, slide on the hub/spindle, then torque to spec within 5 minutes. Let it sit for 24 hours before going rock crawling.
For removal, you'll need a sturdy 3 jaw puller, or an enerpac hydraulic puller.
Good question, nifty project!
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