"Robert M. Gary" wrote
What happens if the trim fails in the water. You couldn't pull the
boat out of the water without hitting the prop, right? How would you
get it out of the water?

That happened to me once. I found out after I got home that the problem was
a sticky reverse lockout switch which cleared up the next time I operated
the shift lever, but all I knew at the ramp was that I had no hydraulics.
Fortunately my trailer was such that the skeg was an inch or two off the
ground when fully lowered, so I pulled it up onto the ramp with the drive
still down, then disconnected the aft end of the cylinders and tied the
drive up with rope for the drive home. In a case where the drive has no
clearance, I suppose you could disconnect the trim cylinders in the water,
obviously with greater difficulty.