Hi jsaad,
I wouldn't use a two slot carrier if I were you. There is not enough ventilation. I have seen more than one ACS overheat. If you look at the new 5 slot carrier you will see that Avaya has increased the amount of space between cards. The old 5 slot carrier had superior airflow over the two slot carrier. The last ACS I saw "cook" lasted about 17 months. Out of warranty, customer bought a new card and 5 slot carrier. I looked at the old unit, the power supply overheated.
Just my 2 cents, Chris