Tell the parts guy that model numbers NOW are not the same as back in the 60s, also tell him he needs to look up GMC Truck in the books and NOT Chevrolet. If they still tell you your worng, tell them to come over and look at your truck.
Q. My question is if the 3/4 ton 1500 had a full floater dana 60 rear axle?
A. Yes. Do you not know what a full floater axle is? it is any axle when the shaft the turns the wheel can be pulled out with having to put the wheels and drums, the axle is floating in the housing and does not support any weight, the weight is carried on the spindle on the axle housing.
Rear Drive Axle Information
If your looking for brakes try the
Known Good Part Numbers
page of MY website.