Take the pin out of the shift rod (that goes under the carbs) and push the rod towards the port side. That will let the shift rod come out of the clevis.
i pulled the clip and the pin came toward port side but it appears there is a sleeve with a set hex head on the end holding it in place and i cannot imagine how to get to that with a wrench
If you push the shift rod to the port side it'll release the lower unit shift rod. You may have to jiggle the rod going under the carbs. Go to the Evinrude website and look at the parts diagram, you'll see how it works.