Congrats! I'm sure the search was not easy. I remember the original turbo for 020 was for sale a few years ago.
If you're curious, contact Doug Nigro at GNX registry to run the serial # for your new turbo. It might be interesting to learn if this turbo was ever assigned to another GNX or learn its history.
maybe stating the obvious....serial # is on the compressor side backplate.... all GNX turbo serial #'s were recorded by ASC/GM....Doug has those records....gnxregistry dot org