'89 Pirata - Transmission stuck in forward

I'm looking at buying an '89 Pirata.

The transmission is stuck in forward. I knew this before I saw the boat and figured the clutch wasn't engaging. When I saw the boat there was oil in the hull all around the engine/transmission but the motor started right up and sounded strong (351 Windsor with around 460 hours). I was a little concerned about all the oil that I saw. The floor is solid with no detectable soft spots.

Any ideas what could be going on with the transmission and the cause of all the oil?

Thanks!