hello i need to find a area to install a gauge i have in my car. i have a safety 21 6 point roll cage in the car so that illuminates my a pillar gauge pod so i decided to try and mount it on the cage along the a pillar. i know autometer makes a cage pod but what size do i need? curious if anyone has gone the same route as me. thanks!

 

The cage is 40mm. If that helps. I beleive the 1 and 5/8" pod works. I'm pretty sure that's teh one I have.