Saving Old Seagulls

Had an excellent first day out with my newfound 55. It recreated the vibe (and vibration) that I enjoyed during 25 years with a model 170. I changed the gearbox oil (was milky tan) with fresh 90 weight according to instructions before use. After use I had the motor stored horizontally in the the back of my truck, resting on its tank, prop facing up. I was polishing the lower unit and turning the motor 90 and 180 degrees to do so. I noticed about 2 Oz of gear oil had then leaked. This was only after I rotated the motor. I had also moved the clutch lever a few times. The fluid had remained clear after use. Question, is this normal, and if so does the motor being in or out of gear prevent this? Everything I read mentioned water being abe to enter the gearbox, not external leaking.
also, I was Dissapointment with the speed obtained. 700 pound 17 ft oday daysailer. I've had a 5 yamaha that hit about 5 mph at half throttle and an old evinrude 4 that did the same at 2/3. I realize these motors are two cylinder and larger. The seagull at half plus pushed the boat at about 3 and even though I could give it more throttle, wouldn't go faster. My thought is that the prop is too deep? I used a heavy duty hose clamp to hold the motor about 5 inches higher for the next time out. I'll fine tune that height when I remount the motor. Should that allow the motor to push the boat faster? It ran well, it just hit a wall of sorts speed wise. Thanks again for your helpful advise.

Raised the motor a few inches and changed the angle one notch. Also calmer water. Guess a 3 hp single won't push a 17 footer to hull speed, but it does well enough.