My exhaust system is much like the others, nothing special. Shorty headers, going to 2 1/2" mild steel u-bends tig'd together, a X pipe under the output shaft made out of two 90 degree bends, and some Magnaflow mufflers connected with V-bands. It runs over the axle and out around the gas tank extending all the way to the rear of the frame ends.

I made my hangers and mounts so that they are free to float allowing front to back movement but no side to side movement. I was shocked at the amount that the exhaust system grows in length with temperature. Cold my pipes end 1/4" before the frame caps, and after it's driven they are 1/4" past the end of the frame caps, a full 1/2" of growth. I think you would want to allow some expansion movement so you system is not trying to break apart with the expansion heat cycles.