this can be done but its not so easy to set up!
map all as normal in ports and pins
the limit in the homing direction and the home switch need to be connected together to the same input pins (linked together)
the other limit input need to be wired into the "closed position" permanently
make sure you have use limits as homes checked on in mach 3 ports and pins
ive set up a few machines like this and it always turns into a head scratcher.!!! do one axis at a time
if it doesnt reverse off the limit switch then reverse the limit wires.
good luck.
like i said, it can be done but always seems a bit of trial and error to get right.