capchaos, firstly, nice work!
Secondly, I'm setting about modifying my CSR Elite too. To start with, I've wired a FREX SHIFT+ to work with Xbox 360 direct through the wheel like you did with your DSD shifter, and have also ordered an SLI Pro and DSD Sli pro tab. How much wiggle room is there between the bottom of the SLI pro pcb and the top of the CSR Elite wheel base? I'm running a stock wheel for the time being until I figure out what I want to do.
I'm guessing that the buttons on the wheel itself are PC only, and the only 360 compatible buttons are on the upper buttonbox? I really need to keep stuff on the wheel itself, as I've already got a DSD button box on the way.
You should really put your works into production. They're amazing.