I've heard rumors, but I haven't seen it done. Any idea what would be involved? My brother's 03 that I just built the motor in has about 140k on it now. No transmission problems, but I am aware of the lack of parts availability for the 5600. He loves the truck and wants to keep it for a long time. I've got access to an 05 with a G56 with less than 20k on it that will be going back on the block soon and I can swap the transmissions if it is worth the trouble.