Kinda funny how we continue to work on the same things Dale. I had to do that exact thing with my mechanical linkage also. My lever at the firewall had to be extended by about 4 inches and shifted to miss hitting the fuel rail and fitting at the end of the rail, and the linkage rod has custom bend in it also. LS or BBC, doesn't matter.
I also just finished my cold air intake which is similar to yours, except I used a 17" aluminum cake pan. My filter doesn't sit quite as high as yours(maybe 3/4" lower), so I'm able to run an aluminum "bubble" top that promotes air flow instead of the filter top. My plan is to do 2 runs on the chassis dyno with the cold air unit in place and 2 runs with just a standard filter base just to compare. I'll let you know what the difference is.