BB,
find pics of TTswitches here:
http://www.ferrari-talk.com/discus/m...tml?1064757818
maybe Ferrari just calls them temp switches.
The crossover flap should normally be closed, you should be able to check by drawing a vacum on the actuator valve underneath the IM. The top won't come off without first taking the entire manifold loose (of course {

}) or maybe just one side minimum? very difficult with engine in the car, but possible.
Can you get some start-up CO readings?
Regards, JRV