I'm running a Avid Pro 48x96 using Mach 4.  I am trying to learn to make things more efficient.  When I do a tool change, and have to use the touch plate to set the bit height, I have to jog the bit over from it's ending point (I assume to be 0,0) to jog the machine to center the bit on the touch plate which takes time.  I am sure that I could add a script or change something to have the bit end on the previous g-code to stop over the center of the touch plate in the x and y plane.

Any advice on how to accomplish this?

In theory that is a great idea but many times you wouldn't want to re-zero over the center of your work.
Many times I need to jog to an area that has the original raw material height.
Many times this is not in the center of my work.

Add a line or two of gcode at the end of your program to go where you want it to go? You'd probably have to use machine coordinates, like

G53 Z123.456 (someplace safe, like way up at Z machine coordinate zero, or where your machine zero should be!!!)
G53 X123.456 Y123.456. (over your touch plate)

Remember G53 is modal, one line at a time!!

These would be relative to your machine home position, assuming you have home switches and home the machine!! Depending on what you use to generate gcode, maybe you could edit the post processor to add this at the end of every program.

Or, a button on your screenset to go to a preset position. Press the button after the program ends, or really, any time a program is NOT running. Might want to put a safe Z in that one, too. And those will need to be relative to machine coordinate positions, really the same code as if it were in the program, so you know where it's going without regard to work coordinate positions, like G54, G55, etc.

If you don't have home switches and home your machine every time you start it, all these bets are off!!! You're sort of screwed in that case because you never know where anything is relative to a "home in place" position.

Thank you very much.  I am learning, just trying to get educated on how to do these things! I appreciate it!