I got mu tuner in 5 business days. It took them only two days to get me my custom tunes after I sent in my HEX code. I'm not sure how fast it would take to get tunes for the X3 or at troyer performance.

 

I am also trying to keep my exhaust quiet. I will have cutouts for the drag strip and a 97 tune that goes with that. As long as your exhaust is longer than the length of which scavenging benefits you you can dump it wherever you like. Just be careful of wires and sensors. I have an 82 with the 302 and put my mufflers under the cab and ran turnouts right after the cab. I strongly do not recommend this. On a long red light you get fumes and smell and a whole lot of noise. I had an old bravada which I dumped toward the rear bumper and I agree, it worked nicely.