Hoping someone else will chime in here, but shouldn't the forks be at the top "edge" of the top triple clamp in stock form? Then the triple plate clamp goes on top of that. So if you look inside the "holes" of the genmar riser that's on your bike now, and the forks are just flush with the triple clamp down there, you should be able to just raise the forks 3/4" from there. IF they aren't at the top of that clamp, then yes, you should find a way to start over. I'd be willing to bet they are flush right now, and the previous owner installed the Genmar to raise the bars, not raise the forks..