Hotrod,
There are 2 options, finding the factory OEM setup or purchasing the aftermarket setup from Bendtsen's Transmission adaptors, they sell a complete kit, adaptor, flywheel, etc. including a start (long throw gear), the new setup with run you about 1,400. One of our members may have one they want to sell.
https://transmissioncenter.net/shop/...ion-gm1000201/
You will also need a torque converter and a HELPER, because the swap while a simple and direct bolt in requires an extra set of hand. I did the swap over 2 days and paid a friend a case of beer, paid after the swap (less I be missing a bolt
. You will need to make the rean transmission support, cost you less than $10,00 made with 2"x2" angle Iron from Home Depot. Also, you will most probably need to shorten your propeller shaft (driveshaft) because the length of the 700R4 is longer. My total swap cost was less than $700. I found an oem adaptor from another trucker.
You could buy my setup for $23k but the truck comes with it