Has anyone tried to swap the tach to the left and put the speedometer in the right position? They are the same size but would it work?

 

The two units will interchange and fit in the other holes, that's not a problem. The thing that comes to mind is the speedo cable. It may not reach to the other side. The tach is electric and not an issue. Give it a try.

 

Not to mention the odometer reset cable may need modification.