October 29 2016: Today began with determining that I may have indeed made yet another mistake; although once again nothing that cannot be rectified or one that is irreparable.
The plans from what I read after sheeting the majority of the hull call for the transom area and lockers to be sheeted and emplaced first. That means the four half inch ply transom meant for the motor and the walls for the inboard side of the split transom emplaced before sheeting the hull.
Since the interior transom called for an angle of 12 degrees, I figured it would be a good time to have my wife come out and help. Being she is the math whiz behind this consortium of effort. She readily verified the drawing and we soon had the exact location and emplacement of the transom. We also had the exact size negotiated; since I simply created a four ply transom from the hole between the two split pieces. Evidentially that is not necessary (its way to large) and the four half inch plywood piece for the motor is actually somewhat smaller than the hole.
I cut the big ole transom down to size with my sawzall and planed the rest to the correct size. The locker sides were cut for the most part without issue and dry fitted into place. Once we had everything ready to go and fitted; epoxy was mixed. We attached the side pieces of the lockers first with screws and epoxy before fitting the beasty four ply middle section. The honking transom piece took some persuasion with a mallet and muscle to fit appropriately. Savannah and I screwed and epoxied the crap out of it until we were satisfied it was emplaced securely.
While there are still some gaps to contend with, I have every confidence that they will be dealt with accordingly. No doubt using copious amounts of both timber and epoxy!