If you have enough extension that extends behind the clamp, you can use a system like the J3 brackets from Profile to mount directly to the extension.
If you need them really wide than I have modified the all-in-one new J3 clamps (same that come with the Viper, et al.) cut off the base bar clamp section, a little clever grinding, some black spray paint and your left with a ton of position to extend wide. I have several pair of these that I have made for 3T and Speed Concept 9 series and other difficult to get wide bar systems. The other advantage to doing this is you can bring the pads back further.
Retul Certified Master Fitter, FIST certified fitter, Owner of Hypercat Racing http://www.hypercat.com
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