Got the brake pipe installed yesterday. The runs have changed from the video. I managed to find some pictures in the build manual for a mk3 (although weirdly they appeared to be a mirror image to my car!
In doing this work I used 4mm rivets and drilled 4mm holes to accomodate them. In order to protect the steel I used grease to fill the cavity before putting the rivets in place. I probably should mention at this point that in doing the work this week I have relied on a lot of sourced imeprial bolts. As luck would have it there is a specialist imperial size supplier (Margnor fixings) just down the road. They have really helped me and I wouldn’t hesitate to reccomend them.