Thanks for the info - unfortunately the answer I was suspecting but didn't want to hear. I'll be pulling the transmission tomorrow night after racing.

This will be done while in the water. I built a brace that will screw to the aft engine bulkhead and built up the surface with a wood block so it presses aft against the stainless collar on the shaft seal. This will allow me to loosen the allen screws in the shaft seal collar and slide the shaft aft when I remove the bolts from the coupling at the transmission. I'll use EB Green tape around the collar joint as insurance while the shaft is loosened. I should have the fixed transmission back from Kiwi Marine Services by Friday to reinstall so I don't miss the weekend!