Hi. I’ve bought one of these to try as an alternative to my expensive carp top kits. I measured the diameter ( as best I could, given how small it is). I bought a 3mm Maverick internal bush which turned out to be just too big, so I bought the next size down: 2.8mm which I’ve Just found is too small! The top kit had an external bush pre fitted which I had to cut off, ( I don’t like externals). Anyone had this problem and found the correct fitting?