Short version is my brand new (from Biqu/BTT) SKR Pro v1.2 control board has a faulty Z port, and while I am waiting to deal with getting it replaced, I was thinking to move Z driver to the empty E2 port.
Where in Marlin 2.1 configuration would I go to find the port assignments to do this? I couldn’t find anything in Configuration.h or Configuration_adv.h
the files are in the same place as configuration.h and configuration_adv.h.
I do not know what to change in your case but with printers , ramps 1.4 and arduino mega boards I sometimes change pin numbers in those files