I do now because the chassis cab has the fuel tank where a pickup would normally carry a spare. When I had my short bed Arctic Fox TC on the chassis cab, I had sufficient room between the camper and headache rack to carry the spare. Going to a long bed Host TC changed where I had to store it. You need a SuperTruss that is at least as long as your tire diameter to get a enough of a mounting base. I still am not convinced that mounting a spare in front of the grill does not diminish cooling capacity because of restricted airflow.
https://www.rv.net/forum/index.cfm/fuseaction/thread/tid/29117589/gotomsg/29250087.cfm#29250087