Thanks Ron. Finally found help. I have a few questions.
1. Is your single 11" placed in the center, under the spine?
2. Can your single 11" hold the temp in a traffic jam? ?n what ambient temp?
3. Which part of the cage do you have to cut? Is it the end towards the front of the car because the clam slopes narrows.
4. How much more clearance do you still have at the center of the motor?
5. Can you take a pic with your cellphone and share so I know how much clearance from the side you still have.
I used a single Spal 30101500 11" Straight Blade Low Profile Fan -- It was the biggest that I could make fit. It took a little bit of dremel work on the fan cage to get under the shroud on my Exige.
It works very well, pulls the temp down 15 degrees in less than 10 minutes at idle, don't think a dual fan system would do any better.