All my 3/4 and 1 tons are open drive from the transmission to the rear, nothing is enclosed, all sm420 transmissions
That’s 1948-1953 years in my collection
OP has a Canadian gmc 1954
But the small 1/2 tons did have tubes for some years I think
That’s why it would be useful to know what specific door tag information in on the truck in question
-s
