I prefer the post 68 760s and the early 7600s ( pre 1990 ) . Now as far as the 7600 being an upgrade on the 760 , ain't so . The only reason the 7600 was redesigned was because they changed the bolt for the 7400 as an improvement over the 742 , which it was ! They changed to the 7600 , just because they had always used the same bolt in both the 760 and the 742 and decided to continue doing so , for obvious manufacturing reasons . 760s never had a bolt problem , it was the 742 that needed fixing ! The 742 and 760 had 9 locking lugs , the 7400 and the 7600 have two , There was never a lockup problem , it was a wear problem , and only on the 742 .