You can hollow it out, I did it on mine a while ago, just be aware that your 2nd one will also plug up eventually and you'll have to do the same thing. You're going to want to put an extension on where the O2 sensor screws in to get the sensor out of the exhaust stream, otherwise you will get a check engine code.

2001 Sportage, TJ 106's, Everet spacers and bumpstops, Bilstein shocks on the rear, cone filter, Crager wheels, 235-75-15 Goodyear tires. Custom front winch bumper by Dave Scott. Currently DOA, but it is a work in progress.
2011 Kia Forte EX