That would depend on how **** you were. When I did mine, I swapped out the entire fuel system and all of the electrical.
Just to get the motor to sit on the frame, you're going to have remove the motor mounts on the frame. The right side unbolted but the left side was riveted, so I had to drill out 1/2" rivets. That sucked. The core support is another thing that needs to be swapped, unless you run the little radiator the gasser had, which I wouldn't do. You'll need to add the second battery tray which means you'll also need to swap out the washer juice container and coolant overflow.
I'm thinking the rear drive line is thicker as well, but I might be wrong.
If you really wanted to do it, I would suggest getting a donor truck and taking your time. It took me from Feb to June to do mine working on the weekends but I was also fixing things as I went.