you mean the HO-52/HO-72?
Yup, that's the one... pretty sure the HO-52 is for 3/4 tons, HO-72 is one-ton trucks. I'd hafta research it but I think the only difference is the axles (or maybe just the brakes?) -- the punkins are the same. btw the tallest ratio you'll find is 4:10, then there's 4:56 and lower, I think maybe 5:38... So yeah Nate, mine's HO-52. btw if any of you guys runs across an Eaton with a posi, snag it!! They are quite hard to find.
Wish I had a need for that Craigslist truck; if it's as clean as it looks in the pics, that's a good deal, esp. if it's a 3/4 ton. My truck's a '72 but I really like the hood/front end on '67-'68s. Hmmmm, wonder why it hasn't sold yet?