Hi Kevin, just saw your post from last month...The person I bought mine from has had to do that on mine.
In a nutshell, you have to remove the bed, then the axle nuts and pins have to be removed.
The nut you have to access, in between the frame and tire, provides almost zero access for a wrench.
My neighbor had a special wrench made by a machine shop just for those nuts but prior to that he was able to remove them but he said it was difficult.
After you remove the nuts and pins the assembly will fall free but there is torque on the assembly that you have to relieve, removing a pin I believe does that.
The axle R/R is relatively simple after that.
Hope I didn't confuse you and if you have specific questions during the process, feel free to contact me and I'll ask him for the answers.