Hello Doug,
Have not replied to previous trailer posts as don't need a trailer to use at a boat ramp nor tow it for long distances, just crane up-dowm my Rib which sits on a simple trailer and towed at a distance not greater than 60 meters from where it's stored to the pier/crane. Wheel bearings are a must change if never before has been serviced, grease the new ones with a proper water grease and re grease them from time to time to last longer.
Female connector's o'rings with time and constant hookings on the male connector will be screwed and let air in and motor hesitate, miss at higher throttle settings. Al least Tohatsu's connector behaves as such don't know about Yam ones. If you prime the bulb till firm and there's no fuel spills on the entire fuel line/ciruit shouldn't be a notorious issue while at idle.
CRC decarbon should make the motor to idle much smoother, once ready to go, let me know. Was checking the posted transom's pics, out of curiosity how good are you cutting, filing an alum transom ?
Happy Boating