I went with a single flywheel kit with a heavy duty upgrade. It's made for extreme heat and has a heavy duty clamping capability so it can take the torque of the Cummins. When it engages, it stays engaged. It's supposed to be good for the life of the truck. I'll let you know in another 200k how long it really lasts.

“In a time of deceit telling the truth is a revolutionary act.”
― George Orwell

It's not over when you lose. It's over when you quit.