Converting a dual rear wheel axle to a single rear wheel

[1964c20]

Hi everyone! I just bought a 1964 Chevy C-20. It has dual rear wheels and I'd like to convert it to single rear wheels. Is this something that can be done easily? All the trucks I've owned have been SRW so I'm not familiar with DRW's. Would I need to replace the whole axle or is there parts I can buy to convert it? I also want to get new wheels for it so how does that factor in with different lug patterns? What is the best option? Any help would be greatly appreciated!