I know a few of you have done this, Owain? so after some advice and tips.
The ones I have require an 83mm hole making, but the vent is about 95 outer, but inner section is 83. Is it just a case of wiggling the vent into the hole? If so, once its there, is it nice and tight? Dont want to pop out the vent and it to come out of the window

Cheers
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Chris1999 China Gti6 Supercharged

2000 Bianca 306 Diesel [Work runabout]