It wasn't hard, I did it with a 4.5" angle grinder, a 110v flux core welder and a digital angle finder with no idea what I was really doing and that's it. It was kind of a pain in the ass if that makes sense though. I would put a driver's drop tacse in it before I did it again. My issue was I had way too much money dropped into my dual/lefty combo that I couldn't recoup it due to low amount of potential buyers and Toyota parts have gotten stupid expensive, so my option was to flip it. If I didn't have those cases, I would have thrown a gear drive case behind a crawler at it and run it pax side drop. If you want shoot me a PM and I can talk to you on the phone on the pros and cons of it.
I have it kind of documented here in my build thread, and really documented on Tacoma world. I also used ZUK build thread on yota tech as he did the same thing right before me.
