Exhaust tacking

Using the measurements in the last post I went down the exhaust shop to discuss options for reducing the sound to the correct levels to meet ADR. After a bit of thinking and a lot of measure we worked out that a cat and 3 mufflers would fit along the side of the car. Hopefully this will provide the silencing required. The pictures show that the tacked exhaust. It is going back down the exhaust shop for them to do the final welding. I have found a sound level meter (which measure dB) at DSE for $40. I am thinking a purchasing it to measure the sound output to check if I need a forth muffler under the car. The only concern now is how to get the exhaust to exit on the right hand side or the back of the car with two and half pipe. I am guessing a bit of creative engineering is required.