Need a new torque converter, and flywheel.

[Cdbformula]

I want to hear everyone that has felt with this problems advice please. I have a 99 f350 with about 400,000 miles. The engine is still strong, it is all interstate miles. The truck never towed anything besides the occasional trailer. I started hearing a lot of chatter and for awhile it would come and go. Then one day while doing about 75 on the interstate it just quit pulling. I coasted to the side and the engine was still running but the truck wouldn't move. I killed the engine to look things over and tried to restart it but it sounds like the starter is spinning but it he engine isn't spinning. I haven't pulled the tranny yet but would just like to hear any pointers or advice on the matter. Thanks