This is what the original owner said about the shaft that was in it.
lengthened 85 DC front minitruck shaft, with an fj60 slip yoke(huge u-joint),
Right now I'm running the spare that came with it cut down. It's single cardine and has the larger joint on both ends that matches the fj60 slip yoke. I'm having some issues with binding since I put the rear disco on and legnthened the driveline by nearly 3 inches.