Rough idle could be caused by a few things, ecu being one of them, but without any form of mechanical testing and cleaning who knows. Simply opening the case and looking at the circuit board of the ecu would solidify your first step by finding the most common cause of blown or leaking capacitors.
Live in the Montgomery area, it would be great to get some help when needed buy someone relatively close. I have a 92 STT 5M, with a rough idle now and I'm going to have the ecu remaned first. What say you?