i,ve just finished fitting an MC21 front end, and a MC18 rear to my 16.
the 21 fits with just a swop of the stems. the 18 rear only needs a small spacer made up to fit. you loose the speedo putting on the 21 front, but i,m working on that one. its worth the work to uprate the suspension and brakes. you also get wider rubber you can also fit the 21 17"rear wheel.