A-833 OD in Aspen... not the right one?

I have an A833OD from an 81 D100 pickup in my 68 Cuda. The only difference is the length of the main shaft and tail housing.

You need to fab a custom bracket that bolts to the rear mount and positions the shifter forward to the a-body position and shorten the drive shaft. Depending on what you had for a tranny you may need a new slip yoke to match the output shaft splints.