Howdy Joe,
Ok, how about something like this, keep in mind I'm not a CAD expert and I tried to come up with something based on parts used with your 2006 machine.
This did add 1 1/2 inches to the overall height, but the back plate remains at the specified dimensions.
2004 ACAD File
z_axis_slide.dwg
2000 ACAD File
z_axis_slide_2000.dwg
Like I mentioned before I've also been planning a mod to my existing machine or maybe a new machine so any suggestions are always welcome!
Bob