The Truckstell units were a dealer or custom shop installed option that went in the torque tube as Jeff said - meant for cars only from about 41 to 54. I have read of them being installed in a few 1/2-ton pickups and suburbans. Rarely one pops up on ebay. I have imagined installing one in the front torque tube of my 3/4-ton pickup. Dunno...
Here are a few pictures of one
one two three
