I bought this thinking it would bolt right up to my 1999 GS. I was told it was taken off a new 2008 GSXR 750, presumably to be replaced with a more track-oriented one, but I have no way of knowing that.
The mounting holes are the same distance, 320 mm, or roughly 12 and a half inches. Problem is, the base of the clevis is very thick, so there's only 23 mm of space, rather than the 30 mm on the GS.
You would need a cushion lever from the GSXR for a proper fit, but that's a tad narrower than the one on the GS.
Bottom line, it's not a project I'm willing to undertake now, but if you're reworking your rear suspension in a big way, this might be the ticket.
It gets in the way of the stock airbox, but if you've already swapped out for a K&N lunchbox, you're probably fine.
Asking $50 US, shipping extra.