Double Z

Hello!!
I am Working on double Z, I have taken 4 axis as X,Y,Z,W. I am using W as my Z2 so W axis is working properly but In my case I want my double z should work like if 
N10T1M06
N14X0.000Y0.000
N20Z10.000
N22G00X-19.087Y264.170Z20.000
 so for this code if T1 M6 is there for every Z value my z axis should run but whenever T2M6 code executed in gcode then for every Z value my W axis should run. 
Please guide me How to implement this functionality I can't change my gcode file otherwise its working properly if I replace every Z with W for T2 M6.

I see two possibilities for this:

1. use a python filter script that parses your gcode file and replaces 'Z' for 'W' depending on the 'T' number
linuxcnc.org/docs/2.9/html/gui/filter-programs.html

2. use a custom kinematic that lets you switch between XYZ1 and XYZ2 and then use an m6 remap to handle the switching automatically for you.
For an example with 3 heads (custom m6 remap not implemented though)
forum.linuxcnc.org/10-advanced-configura...y-and-control#292847

Personally I would prefer the 2. because
a) there is no need to modify the gcode
b) It also works in MDI mode and Jogging
c) the planner does not fall back to one line lookahead (which happens whenever an axis word other than X,Y or Z is used in gcode)
d) with a filter script you would really want to check the output every time to make sure it actually got it right