SOLVED X-axis homing problem : 0,0 is the left extruder, not right

I'm not sure how I went and did this, but G1 X0 Y0 puts the left extruder at 0,0. I've tried
reloading memory, doing this in g-code terminal
M206 X0
M500
and power cycling

I'm printing from each head just fine, but to get the right extruder at 0,0 I need to use MOVE AXIS and go to -38,0

 

I misunderstood this page and followed the incorrect instructions during setup:
http://wiki.e3d-online.com/wiki/FAQ