PK,
Yes, Gary in BR's twin turbo install has an intercooler on the bottom of the motor where the aluminum stress plate originally resided. He has pictures here (or on sixspeed?) that show it pretty well.
The TTP installation puts the IC in the rear trunk, here's a pic:
http://www.t-t-p.de/pics/porsche_kits/engine_986_2.5.700x462.jpg
Eric