It depends on the brand of filter I'm thinking. Some filters have a more flexible rubber compound whereas others are stiffer. Even using a screw driver to help things along (yes, I tried almost every lube known to man...I'll leave that to your imagination) and it was still a bust.
The author notes that you can get a K&N that fits on there perfectly with a 3.25 ID but that's only if you're in the market for a 60 dollar filter. Since I had to go through 2 filters to get it to work, I should have just bought the danged K&N the first time.