just follow these instructions.
HOW TO: Install Boost Gauge into Drivers Vent - Mazda Forums
http://www.mazdas247.com/forum/showthread.php?t=123693832&highlight=vent+boost+guage
use this PDF to remove the vent. i had to use a pair of pliers to turn the inside duct.
http://www.showyourmedia.com/files/1252972295.pdf
here is a good thread about wiring...
Boost Gauge Vaccum Hose Route - Mazda Forums
http://www.mazdas247.com/forum/showthread.php?t=123752663&highlight=vent+boost+gauge+pdf
here is a vid of mine. i used all these tools to install mine.
http://1strule.org/m/110/1252104185IMG_0273.MOV
HOW TO: Install Boost Gauge into Drivers Vent - Mazda Forums
http://www.mazdas247.com/forum/showthread.php?t=123693832&highlight=vent+boost+guage
use this PDF to remove the vent. i had to use a pair of pliers to turn the inside duct.
http://www.showyourmedia.com/files/1252972295.pdf
here is a good thread about wiring...
Boost Gauge Vaccum Hose Route - Mazda Forums
http://www.mazdas247.com/forum/showthread.php?t=123752663&highlight=vent+boost+gauge+pdf
here is a vid of mine. i used all these tools to install mine.
http://1strule.org/m/110/1252104185IMG_0273.MOV