is this a ram 9 1/4 or dana 60?

It is a good rear, check the pin nut isn't loose

This is what dodge had lawsuits over because pinion nuts back off of 9.25's in the 1500 Rams from the mid 2000's and up....Just look it over and you should be good. better yet, get a 9.25 from a Dakota and you won't have to narrow it at all to make it fit in an A-body! Most came with 3.92's and sure grip!