Thought I would throw this out there, as I haven’t come across anyone crazy enough to do this. I found a practically unused (never slept in once) GFC for a 6ft bed Ranger. Only problem is my Ranger is a 5ft bed. It was at the already low price of $3K OBO. Knowing the work ahead, I offered $2K even. They accepted. A friend was driving up from out of town where GFC was, and trailered it up.
So far I have managed to completely disassemble the tent from frame, and taken frame apart. I got measurements from someone who has 5ft GFC, and I very carefully cut side rails to length and reassembled it. Next up is cutting side door panels in half, removing a foot, and welding back together. Then installing tent. It’s gone pretty smoothly. I had watched a lot of the GFC factor tour videos on YouTube before hand to get as much intel on construction as possible to ascertain if this was even possible.