All CAD/CAM drawings Cartesian coordinates convention, x0 has to be at the left corner of table. That should also be the machine coordinates. YOU should not change that.

If you reference home as you are doing, you could set X to length of table (say +240 inch) and NOT zero. So when you g0 x0, spindle head moves away to far end.

If you set that to zero, then your gcodes must have all negative values of x.

I would just move my x axis proximity switch or do what Gerry said.

Then redefine tool change location to x=240, y=0