Jermey,
The hinge pins probably won't come out of the doors easily without a bunch of penetrating oil, heat and force. I am assuming you are wanting to part out the truck and sell the doors. My advice is to get that truck near a shop or garage where you can access the tools needed to do the job properly. Do not cut the door hinges apart. Take your time and don't get in a hurry. After 73 years those hinge pins aren't gonna want to move.
As for the bolts that fasten the running boards to the frame and the fenders, you can carefully cut them with a die grinder or similar cut off wheel. Should be no problems there.
Good luck