OD trans

'71 340 with a '72 2:47. I'm not putting a Tremec in my Duster. I would have to go through all the frustration described above and cry like all those other little girls before I could be driven to have anything but an A833 (which is basically my point). I DO still want to know the register hole size on the Lakewood aluminum LK7000K bellhousing, however, because I'd like to know I could swap in one of the OD's just for giggles.

And you never know what new product might come down the road, like maybe a kit that includes the cluster plus a new first gear that brings 1st to 2.70-ish as an alternative to 3.09??? JP, you paying attention?

So, if you could find one, this would work?

Brewer's Performance - Mopar A833 4-Speed Transmission and Component Specialists

You could also swap an O/D gear set in an early cast iron main case, tighten everything up and just slide it in your existing set up. Passon Performance already made a stronger gear set with O/D, closer splits, and an 18 spline input shaft.