I run a Wix lawn mower air filter. I don't do it so much for clearance issues as that it keeps the intake assembly small in appearance, but it's only two inches above the carb. The filters are cheap, so I change them more often.
I have used the cut bottom of an aluminum sauce pot as the the top before. It may sound crazy, but it's all in the finishing. If you take the most popular no-stick aluminum frying pan, yank off the handle, flip it over and drill a center hole in it, spray paint it white and slap on a sticker, you have something remarkably similar to the Racing beat air cleaner assembly.
