I'm leaning towards mounting the can on the spare tire carrier.
I think I can fabricate something to work with the stock rim hole on my spare.
I can fit two inch tubular stock through it , but I'm not sure what thickness I should be looking for. The tubular would be welded between two plates, one that bolts to the tire carrier (sandwiched between the rim and mount), the other is the attachment for the blitz carrier.

I'm still rolling this around in my head, trying to come up with the best situation for life of the Monty. Thanks for the help.

'02 Montero: OME suspension, ARB front bumper, homemade skid plates & spare tire Blitz can mount, extended diff. breather, K&N air filter, Optima Yellow Top, BajaRack, IPF lights, Goodyear Duratrac 265/75/16's, RUD 4x4 Grip chains