Someone had an earlier post about how he obtained his alias's via identity theft. The first thing that comes to mind for me is working at a bar/store that sells alcohol where you have to check ID's. Your checking birth dates and he could have remembered the full name as well. I'm referring to Curtis Kimball, the Mayo would be easy to remember because it's very different; however, there is no indication he had any employment as a bartender though.
I found a Doe that was found with some items that interested me in regards to Evans case.
Just to clarify, I don't think this Doe is anyway connected to Evans.
http://www.doenetwork.org/cases/969umnc.html
He was found with a stolen ID, which leads me to wonder if authorities ever contacted the real Curtis Kimball to see if he ever lost an ID during the 1980's. The victim also had a list of places he supposedly worked and a semi-autobiography which reminds me of Evans'. None of the info could be verified (except for his most current employment) and I wonder if he had it to keep up with his alias's background much like what is expected out of Evans' autobiography.
Interesting.