Would strongly recommend against this. It can work with modern stems that have a removable faceplate, although this still isn't ideal. But with older forged-aluminum quill stems, this is a good way to mess up your handlebar and possibly endanger yourself. Sorry, no time to explain more b/c it's Christmas and I'm rushed. But I'd strongly advise you to pick up a 26.0mm clamp quill stem. You can do this cheap on eBay and then use it with your Nashbar bullhorn.
Thanks for the advice Tim. I was thinking this would be bad, and could cause the stem to start to crack, and maby the bars too. Well, Nashbar has some deep drop bars [In the right size!], and aero levers for cheap too.