How do I fit a boost gauge in my 97 cat? I think the car is an MY?
Any help gratefully received!

 

If it's a basic mechanical one then you need to cut a suitable existing vacuum hose coming off the inlet manifold (e.g. the one that goes to your dump valve). Then fit in a plastic T-piece, so that the two 'in-line' ends of it rejoin the the hose you've just cut. Then run a long length of the same quality/diameter hose form the remaining 90-degree take-off of the T-piece, through a suitable grommet in the bulkhead/firewall, and onto the vac connection at the back of the gauge.

If you want the gauge to light up at night (if it has on-board illumination), then you need to splice in its +ve power into the car's wiring loom for the switch for the sidelights, and the -ve to a suitable earth... Or splice the +ve to the ignition barrel's 'ACC ON' position, so that it lights up all the time when engine's on, but will go out when you switch off...