Would it be reasonable to put the macro to set the Z height into homeall.g so that you know it’s been set up at the start of every print. So it would be something like

- home x and y

- set gantry height

- save

Then, if the print requests it, it will also probe the bed.

My concern is, if I just set it up as a macro to do this “as and when”, Murphy’s law dictates that the first time I have a power failure, I will not have run this for some time.

If the motors will just run backwards, then why not just connect them that way, and reconfigure in software. Wouldn’t that avoid the need to trim the keying guides off?