Shift is especially good on an AOD. They slip quite a bit stock and are susceptible to heat damage. check out
www.baumannengineering.com - he's got about the best kit going.
Lots of good tech info, too.
Couple good additions you an put in while you're doing your shift kit is the Art Carr "zero leak" 2-3 shift accumulator and an A od servo - available at Baumann, Carr, etc. go in just under (above) the valve body, no other disasembly. About $30+ each.