The customer stated when using PC3 with AutoCAD, the system is saving the plot file to its own directory, he would like it to save to another drive they use for back up.
What is the PC3?
Could your client be referring to Postscript 3 and not PC3? Maybe they want to plot to file using the PS driver.
They can set the folder location in Autocad where they want to plot the image to file.
I could be wrong but that sounds like what you are referring to here.
Is there a workaround for the customer?
Looked at my autocad LT and felt pretty ignorant.