When you put a lot of power through a torque converter, trans fluid temps go way up. So, get a transmission cooler to keep from cooking the trans.
I've got a very mild, non-intercooled Vortech V-2 S-trim blower on my '07 GT automatic and it's doing quite well after 5 months of hard driving and a day of hot-lapping at the dragstrip recently. I'm actually more worried about the heat being generated by the aftermarket stall converter than I am about the hp from the blower.