http://www.elitecaraudio.com/s...pic=1See the two articles entitled "Physical and Acoustic Problems Affecting Sound Quality in a Car" and the one about kick panels.If you are going to fab something, you might as well do it right and make some kick panels. Tweets should be as close as possible, generally speaking, to the midrange drivers so that all the sound waves reach you at the same time. This is also the thinking behind kick panels...minimizing the distance between left and right. I haven't done it myself (yet...maybe after the engine rebuild I'll get to the interior), but there are sites that will help with fiberglassing technique. Of course, with the limited space in an s13 this may be difficult. You may need to relocate the ecu and/or fuse box... I don't know, I haven't made measurements yet and I haven't driven my 240 in a while. It may be too much trouble, but it's just a suggestion.