AC bed rack dimensions?

My brother in law is driving 12 hours to my house to pick up my roof top tent. He is on a tight schedule and was planning on sleeping 6 hours and then throwing it in his bed and leaving and figure out mounting the tent when he gets home. He doesn’t have access to fab tools, so likely he would end up buying a rack.

I would like to build him a rack, preferably before he gets here. The 6 hours he is here would probably be doable but it’s over night and my neighbors don’t want to hear me cutting and grinding. I have a 06 DC but I read that the beds are different enough that I can’t use it for mock up, is that true? I really only need the bed rail width distance and the cab angle starting at the bed rail so that I can make the rack follow the cab. I am not worried about bed length or depth which is where I had always though the beds between AC and DC differed.