I've just fitted some bonrath ones (just need to do 1 screw on each, couldn't do at the time cos car sat too low and I couldn't get drill under to pilot holes, lol) and I found that the k and n tubing fitted inside the hole, just about

As I had 2 of the tubes, drivers runs to induction kit and other runs cold air to engine,
I had to pull the horn towards the opening to get the knn tube round the back and zip tied the
Amb temp sensor to the horn loom,
Reckon the knn stuff is max 80mn diameter and it went round ok, so think you'll be fine..

