The 46-72 is correct. GM used the HO72 up until 1972, then they went to the 14 bolt. The 8 lug HO52 and 8 lug HO72 were basically the same, just different ring/pinion center section combinations.


1954 3600 Chevy Truck
"The Fake Truck"
In the Stovebolt Gallery
More pix on Photobucket