If you run a five speed 2.2 TII SMEC your idle will be 800rpm instead of 900. A 2.5 TI SMEC will run poorly. The cals differ in spark and fuel curves between 2.2 and 2.5.
You can socket any turbo SMEC and burn a custom cal to an EPROM to install in the socket. There is a lot of information on the subject here: http://www.boostbutton.com/turbonator_wiki/doku.php
A Rob Lloyd did great things with code for 2.2 and 2.5 turbo engines. He was nice enough to make it all open source. All you need to do is read, buy a burner and a solder iron.
At the link directly above, you'll find the Boost Button stage cals. There is a Stage II SMEC cal for the 2.2 auto. I'm running that in my TC. It works well in a stock car with the stock turbo, exhaust etc. Stages III and beyond require upgrades to the fuel system, MAP sensor etc.