Street or drag race tranny?
I'm in Bend, OR and use to drag race a Hemi Cuda in NHRA stock for almost three years back in the early to mid 1970s, lots of maintenance on those early slick shifted and Pro shifted boxes back then, I still have some of those parts left.
Is yours a 23 or 18 spline and do you know which year box it is or the low gear ratio? That matters on the input and output shaft bearings
As already said they are not like new manual trannies at all, not really complicated to work on either as long as you know what your doing or can follow using a factory service manual
PM me on here if you want