On my custom there's 2 horns, worse case is the electronic connector is different. (Mine is 2 x single horn each with its own connector)
If you get stuck I'll crawl under and take a photo, I'll bet if you eBay search you'll see both types tho
56 350 2.2 130ps mk7 with 2 side doors
65 290 2.2 125ps custom with 2 side doors
07 350 170ps
Ids v86 licence + v86.04 update + xprog
hereIds map
here