I am trying to spec out the 7 bolts that hold the swivel ball to the axle flange. I believe they are M10 1.5. I need to clean out the inner threads on the axle flange before reassembling. I can't conclusively match them up with any of those hardware store testers, so I don't know what size tap to buy for cleaning the threads on the flange. Some of the first, narrower starting threads are not quite perfect. In fact, at the store, the 7/16 thread tester seemed better than the M10. Go figure! The Rave manual doesn't say exactly. Anyone know for certain what the exact size is?