I have an '89 HO engine in and older truck that for now just has true dual exhaust. I want to add in an H-pipe(or X) for best performance and sound. I have ready about the H needing to be a certain ways down the exhaust fromt he collectors, but haven't seen anything that states if the H needs to be a minimum or maximum distance from one pipe to the other..This beign an old truck there is quite a few obstacles to overcome and I am thinking the H section won't be as effective if it is too long across?