72 XS2 with 2007 GSXR 750 forks. The head tube of the earlier frames are short enough to fit the GSXR steering stem of the new forks. We did the swap on a 77 XS and we had to remove 7mm of material off of the lower bearing cup on the frame to get the same forks to fit. All-Balls offers two depths of bearings in their conversion chart. We recommend using the shallower (i believe 12mm) one for more clearance. This picture has the GSXR axle with SK bearings from eBay. Custom machined inner axle spacer between the bearings as well as external hub spacers to center in the fork. Not in the picture, I am using 6x80 BCD rotors off of an FZR1000 or Aprillia Mille with spacers to center them in the radial calipers. Finally it took 5mm spacers to move the calipers out enough to clear the 320mm diameter of the new rotors.