well my brother has a mk3 (i think) will find out tomorrow and he got an autometer boost guage. we have no idea where to start on installing this so any help woudl be appreciated. we just basically need to know where the wires coming out the back of the guage connect/join to.
thanks.

one ground
one 12volt
switched power source
you need an air line to tap into the system somewhere
i used thin copper tubing and tapped into the intake manifold /upper
the copper line runs in through the firewall via an existing hole . i think it's a heater line , i forget right now

mounting the gauge using a pillar pod is handy
Pillarpod with boost gauge