definetely a sleeper there.
as to how to do it i know theres probably quite a bit involved, i would check out
http://www.l67swap.com for sure, the Intrigue is a W-body, just like the GTP, Regal, Monte SS, and Impala SS all of which came at one time with the 3.8 Supercharged, so the mounts for the engine and transmission should be pretty much the same. The rest would be wiring and lots of it, computer stuff...
I also notice it says hes using the stock Intrigue tranny......very very very bad idea as far as im concerned, thats a stock 4T65-E which is simply not built to handle that kind of power, thats just asking for a blown tranny.
I want to see someone force induct a 3.5, which i know of one person who has talked of doing so, that would be sweet..the 3.5 is a great engine, its a shame theres no aftermarket for it and that they stopped making it.
In my opinion the 3.5 is superior to the 3.8 Series 2 in terms of both power and reliability...having previously owned a car with the 3.8 i can say that is much more "driveable" though do to the low-end torque and flat torque curve..but as far as actual get up and go the 3.5 is better...now the supercharged 3.8 on the other hand....