In the hal file these are the signals needed for spindle orient
Some signals are here for normal spindle operation
loadrt and addf commands not shown here. Don't forget them though

net spindle-pos  		hm2_[HOSTMOT2](BOARD).0.encoder.01.position => near.1.in1 orient.0.position pid.1.feedback motion.spindle-revs
net spindle-velocity 	hm2_[HOSTMOT2](BOARD).0.encoder.01.velocity => near.0.in2  scale.0.in motion.spindle-speed-in 
net velocity-mode		motion.spindle-on => or2.3.in0 pid.0.enable 
net spindle-vel-cmd		motion.spindle-speed-out => abs.0.in pid.0.command
net spindle-angle    	motion.spindle-orient-angle => orient.0.angle   # ORIENT_OFFSET value in ini normally 0
net orient-mode			motion.spindle-orient       => orient.0.enable pid.1.enable mux2.0.sel or2.3.in1
net spindle-pos-cmd		orient.0.command => pid.1.command near.1.in2    ##in vismach
net spindle-abs			scale.0.out => abs.1.in pid.0.feedback
net spindle-vel-pid 	pid.0.output => mux2.0.in0
net spindle-pos-pid  	pid.1.output => mux2.0.in1
net spindle-cmd      	mux2.0.out => abs.2.in
net spindle-cmd-abs		abs.2.out => hm2_[HOSTMOT2](BOARD).0.pwmgen.00.value
net spindle-orient-fwd	abs.2.is-positive => or2.2.in1
net spindle-fwd			abs.0.is-positive => or2.2.in0

net spindle-dir			or2.2.out =>  timedelay.0.in  # the delay is so my directon relay switches during my spindle driver inhibit time
net relay-delay			timedelay.0.out => hm2_[HOSTMOT2](BOARD).0.gpio.017.out	 # Direction relay

setp near.1.difference  0.5	# this was set high for testing

net spindle-pos  hm2_[HOSTMOT2](BOARD).0.encoder.01.position => near.1.in1 orient.0.position pid.1.feedback motion.spindle-revs
net spindle-pos-cmd orient.0.command => pid.1.command near.1.in2    ##in vismach

setp edge.5.both 0
setp edge.5.in-edge 0
setp edge.5.out-width-ns 50000000
net spindle-in-pos-raw near.1.out edge.5.in #not needed v2.8+, use orient.0.is-oriented
net spindle-in-pos 	edge.5.out motion.spindle-is-oriented	
# this will set the motion.spindle-locked bit you can use to initiate the rest of the carousel commands


Before i added the REMAP line in the ini file, i tested the orient command using 
MDI input: M19 R0 P1 and varied the angle to make sure it was turning

In the ini file i added the following:

[RS274NGC]

SUBROUTINE_PATH   = /home/tom/linuxcnc/nc_files/:/home/tom/linuxcnc/nc_files/ngcgui_lib/:/home/tom/linuxcnc/nc_files/ngcgui_lib/utilitysubs/

REMAP=M6   modalgroup=6  prolog=change_prolog ngc=change epilog=change_epilog

ORIENT_OFFSET = 0


and add the python section as shown

[PYTHON]
TOPLEVEL=./toplevel.py
PATH_APPEND= ./
PATH_APPEND= ../../nc_files/remap_lib/python-stdglue/


The files:
due to a hdd crash, i don't have all the sim files so i pulled examples from /master/

in my /home/tom/linuxcnc/nc_files directory i added:

change.ngc which i copied from /master/nc_files/remap-subroutines/
to my nc_files directory

toolchange.ngc is a more complete example of a working tool changer found in
/master/configs/sim/axis/vismach/VMC_toolchange

remap.py and toplevel.py are also in that directory as well as in:
/master/configs/sim/axis/remap/rack-toolchange/python

their contents may vary. i didn't check
i put these in my 'root' config directory: /home/tom/linuxcnc/configs/Sherline/


stdglue.py was found in /master/configs/sim/axis/nc_files/remap_lib/python-stdglue
which i copied the whold remap_lib to my nc_files directory

if you want to use the carousel comp instead of the toolchange.ngc file above
an example of the carousel comp can be found in /master/configs/sim/axis/vismach/VMC-toolchange

toolchange_index.hal 

in the example it is triggered by motion.digital-out-00  but could be remapped to trigger
off the motion.spindle-locked signal after orient is done