Does anyone in the Cardiff area want to fit a boost gauge to my Mk.1 Octy for a small fee

I'm not local so can't offer any help with regards to fitting, sorry. It's worth having a look at Rob's site for some ideas/guidance:

Pimp My Skoda!

GAUGES

Where is the best/easiest place to tap into an ignition live?

I tapped into mine below the steering column. If you remove the trim you will find a number of terminals, I used a multimeter to find an ignition switched live.

You could possibly tap into the radio supply depending on the current you are going to draw.

Will have a look when it stops raining. Cheers VRSPhil

Just a though, my car is getting warranty work done in a few weeks. Would adding a boost gauge void my warranty?

As far as I know, modifications will only void a warranty claim if they are related to the component/function at fault. I.E. If you had a leather re-trim you could still claim for an engine fault as the modification has no impact on the engine. I would check with your dealer though as they like to try and wriggle out of claims.

I tapped into the power at the back of the radio

I tapped into mine below the steering column. If you remove the trim you will find a number of terminals, I used a multimeter to find an ignition switched live.

You could possibly tap into the radio supply depending on the current you are going to draw.

Didn't know about them - thanks Phil, they'll be useful for hardwiring my GPS.

Do your remember wich colors were permenant and which were ignition live?

Sorry I don't. You could use a bulb with a piece of wire to check when they are live if you don't have access to a multimeter.

Do your remember wich colors were permenant and which were ignition live?

If you use the threaded posts next to the relays under the steering column then the one marked x75 (or 75x) is switched and the two marked 30A are perminant live.

I think red was switched live on my wiring and yellow was permanent? I know you had to switch around the red and yellow to make my pioneer switch off when I withdrew the key.

Found an Image to help (from a LHD car but the principle is the same)

Just remove the kick panel below the steering column and it is on the right hand side (or if like me you look at it laying on your back with your feet over the headrest on your left ) Can't miss it.

Cheers lads, took it to the stereo in the end so it will dim with the dash lights now. Found my multimeter in the end which made it a little easier, lol. All i gotta go now is plumb in the vaccum line and the jobs a good un.

Cheers for the help lads