"timW" wrote
And by the way, what the heck is the anti ventilation plate?

It's the horizontal surface above the prop that people commonly mis-identify
as the "cavitation plate."

Couple of ideas on the out of gas condition:
1. Boat gas gauges are notoriously inaccurate.
2. Depending on the shape of your fuel tank, how low the level really is,
and where the pickup is located, you could be out of gas in one trim
position and okay in another, IE your bow raises, your fuel moves to the
back of the tank, and your pickup is above the fuel level, then you slow
down, drop the bow and you have gas again.