Mounting my trans temp gauge was tricky...
I really had to think on how to do it. The only available place was on the dash skirt below the steering column. That would have been less than ideal because the taper of the panel is toward the floor making the gauge difficult to monitor.
Here's what I did...
Remove the push button FWD switch and relocate it to the dash skirt. I put it on the right hand side as far up as it would go and have clearance behind the panel. The wires to the FWD switch were just long enough to reach to the new mounting location.
Where the FWD switch used to be, make a panel to fit that hole. Make it out of metal or plastic. Cut a circle in the panel to accept the gauge. Mount the gauge to the panel and the panel in the hole. TaDa!! excellent mounting location for a trans temp gauge, and... custom location for FWD switch.
Another little hint- Offset the gauge hole to one side to allow for possible mounting of a toggle switch beside the gauge.
Hope this helps...