John,

Here are some pictures I made of the 4" x 4" x 1/8" tube steel frame I built to support the cab of my '58 Apache 3100. I drilled holes in the corner of each of the top pieces of TS so I could attach the cab just like it attaches to the chassis. The 4 locking casters make it easy to move the cab around in and in and out of my limited space one-car garage.

http://s1262.photobucket.com/user/Raleigh58/library/Cab%20support%20frame