* Electrical Differences: The 1993 700R4 likely has a different electrical harness and control system than the 1989 model. You'll need to sort out the wiring compatibility and potentially adapt the harness or use a standalone transmission controller.
* Mechanical Differences: While the basic design is the same, there might be subtle differences in the bellhousing bolt pattern, input shaft length, or other components. You'll need to verify compatibility between the transmission and your 1989's engine. A different torque converter may also be necessary.
* Computer Compatibility: The 1989's engine computer (if it's fuel-injected) might not be compatible with the 1993 transmission's signals. This could lead to poor shifting or drivability issues. You might need a standalone controller or a modified computer.
In short, while it might be *doable*, it's not a simple swap. You'll likely need a good understanding of automatic transmissions, some mechanical aptitude, and potentially specialized tools. You'll also want to research the specific differences between the 1989 and 1993 700R4 transmissions to ensure compatibility. A professional transmission shop would be the safest route to ensure a successful installation.
