The most inexpensive way to go would be to put the MOPAR blow off valve kit on. Many on this site have put this on their GTs. I personally have a HKS SSBOV on my GT. I got it before the Mopar kit was available. The Mopar kit is every bit as good as any aftermarket BOV at a fraction of the cost, and except for one bolt that is hard to get at, its easy to install...
Here is a pic of the HKS SSBOV installed on my cruiser
