Mike,
The New Port conversion kit mounts directly in place of your existing vacuum motor and operates the wipers using the OEM cable drive system. If you are looking to replace the cable drive system, you will have a much more involved conversion. If your cable drive system is intact and functioning, then the electric motor conversion is a direct bolt-in replacment. You can check the function of your cable drive/transmission system by removing the vacuum motor and turning the cable drive shaft link with pliers (carefully and slowly) to see if the wiper blades are moving correctly. The electric conversion kit comes with a 2-speed switch that can be mounted below the dash or can be controlled by the original wiper switch with a special shaft kit (also provided by New Port as an option).
Good Luck,
Dave