I've just taken delivery of a Topper TNL-100A 2 axis lathe with a Fanuc OT.

After getting the Z axis ball screw rebuilt it's up and running pretty well other than the spindle runs in reverse.

I have to use a M04 to get it to run correctly. And the manual buttons are also reversed.

I tried swapping power wires to change the phase rotation but that didn't work.

I looked at the programs the previous owner left in the machine and they are all using M03.

Is there a parameter than can be changed to fix this?