bankiforme

I have a 1994 gs00. The ecu that the car came with is fried the number is 89661 30691. I went to a junk yard and pulled an ecu from same year gs 300 but the ecu nubmer is 89661 30690. What is the difference between the two if any. Ive seen a couple sources that say its interchangeable but i cant find anything that just says they are. Or provides the diferences. Any suggestions would be great.