I did this. But yes, you'd need to make cut-outs in your bed base to suit. Buses are all different, most of them don't have this problem because they don't have those vents and the Y piece is shaped to fit under the floor. Maybe right, my memory is what it is, it was 20 years ago when I had my Westy interior apart and I sold it 10+ years ago so I can't look. Surprised I can remember where all the fixings are TBH.