I think a cage sounds good, I'll be sure to ground anything not welded to the cage. I have a few pieces of 3x3 1/4 wall tubing that should be a good start. Also have some rubber bushings for large compressors that should help with the noise........ heavy cage and rubber bushings might make it quiet and keep it from moving much. Thank you again!!!!For a short link, #14 would work just fine. The issue is voltage drop, not heating per se. The over-current will not blow #14 like a fuse.
I agree with getting it up off the floor. I think a cage would be easier than a shelf, given the weight of the motor. Make a stout little base, and maybe a little ventilated cover?
If it's too noisy when running, one can mount it on some rubber vibration mounts, but don't forget to provide a flexible grounding strap from motor frame to base and cover if they are metal. Everything metal must be grounded.