Hifirush

While I agree blockers will get you by, a proper crossover will make your system sound much better, directing the proper frequencies to the tweeters and the mids. I have done both and in the end, a crossover sounded MUCH better, check our Ebay or Parts Express or even Crutchfield. If you have any decent car audio shopd near you, they may have something for you as well, or may be able to design a pair for you. Good luck!