Can you please describe the problem you are having?
Does one of the touchscreens not work at all, or do they both not work?
Is the calibration off (as in you touch one place, and it acts like you've touched a different place)?
You can try swapping the touch overlay between the right and left sides. That will tell you if it's the overlay that is having a problem, or if it's the controller.
I have swap the touch overlay between left and right. The problem is touch overlay.It is not calibration off. The same area can not touch. Where can buy the touch overlay.
The touch overlay used in the HogIII is custom made for the console, and only available from HES. Where are you located in the world? Your dealer should be able to help you get the part.
Before you do that though, make sure the overlay is properly installed that that nothing is touching it. If the overlay is mis-aligned with the bezel, the bezel can sometimes press on the active area and interfere with the touch sensing.