5.9 mag into d250

I would think you will need one from a 2000 Dodge truck with a 5.9 Magnum. If you buy a new one, be sure to specify that you have a 5.9 gas engine, not a 5.9 diesel. The flywheel from your 360 won't work. It does not have the notches needed for the ignition, and the balance on an LA 360 is way different than a 5.9 Magnum.