Sounds like a good plan to me. If it gets too cold, you can always turn it down.
On the other hand you could always replace it with the model 2-55 air conditioner. I have one on my daily driver (97 Merc - nickname is toilet). Two windows down at fifty five miles an hour. The AC gave up the ghost about a year ago (leaks) and the compressor decided it wanted to fry itself.
