I know this is sort of off topic but anyone has any ideas, I would appreciate it.
I've seen a few of these on the web and some were free. If the g-code file is nested it can get wierd, if it's a single part you could do it with a machine programming manual.
I actually wrote a program that converted NC tape files to DXF to inspect the program from within AutoCAD as a virtual vernier. Back then there were only a few g-codes being used. Later everybody had the ability to plot the tapes or programs as you wrote them.
Here is one that I have used from a CNC forum.
You will have to register to gain access to the site by registering but it works.
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