I have this set-up in an E-body. As others have said:

The tunnel has to be modified. On my Cuda, there was no way the driveline angle would have been close to correct with out the cut. i just used the extra tunnel piece they sent with the kit. sorry no pic. Then I used all the spacers that came in the kit to get the tail-shaft up. 2" total I think.

TTI does make an angled reducer to help with the exhaust. I think it's angled 6 degrees up. If you search there is a thread on it. But if your collector is on the ground it probably won't help much...