5.9 Magnum into a 73Duster

The 99 ecu will freak out unless the trans has provisions for a crank sensor and everything. If you are going with a 518 you might have to talk to hemifever on the moparts site about doing a sct flash for you. This will let you run what ever trans you would like. I have the wiring codes for a 2000 dakota RT not sure if it will match up to your 99 or not. The whole manual is 100 megs so I will see if I can seperate it out for you if you like. PM me if you would like this portion of the manual.
Rob