Steve,
G'day mate!
Depending on what exhaust system that you have, I don't think 2 1/2 inches on the end that the peg attaches to is tall enough. I know on my stock Triumph Longs, that wouldn't be enough in height to clear over the pipes. But the other dimensions that you stated sound about right.
I think you'll see, looking at the pics with my hairy hand holding the tape measure, that you've just about got a handle(or footpeg...as the case may be) on it.
Cheers,
Dwight
