Summit should have the shifter and linkage kit you need or try Brewer's or Passon. It ain't cheap. You will also have to fab up a mount to put the shifter in the A body position, unless you really like banging your knuckles on the dash or having the shifter between the seats. Almost easier to swap the output shaft and tailhousing. The smallest bearing retainer you can put on the OD case is a 4.80" due to the spacing of the mounting bolts. That won't help you much since that retainer was only used on big blocks and hemis and wasn't produced in large numbers. There were plenty of OD bellhousings produced in both smallblock and slant configurations in F bodies (Aspen/Volare) and pickups/vans. Make sure you get the clutch fork with the bellhousing since they are a little bit different than the normal 4 speed one. Hope this helps.
