4DBG ECU is currently in my EF Futura I6 auto wagon 3.23:1 diff. According to what I can find online, that ECU suits a sedan with 3.08 diff

I have a 4DCC from a friends Fairmont he said I can try (I have some electrical issues I am trying to resolve). Is there likely to be any fundamental changes in the vehicles behaviour if I use a Fairmont ECU (4DCC)?