Cooler air is better. But that bucket isn't going to cut it.
Also, in a closed bilge situation like a boat, more air (hatch cracked open) is sometimes helpful depending on the situation as the engines may not be getting enough volume of air from what vents the bilge has provides.

I too ran the Shootout quite a few years and had the same idea’s

I had twin 575s and after about 45 seconds to a minute, they would fade away a couple hundred
rpm with the hatch closed, raise it a bit and it wouldn’t happen, after eventually ripping the hatch off, there had to be a better idea

I ended up fabbing up a plenum that attached to the underside of the engine hatch, the opening was the
size of the flame arrestor, the plenums we’re ducted over to each side engine air intake on the sides of the boat.

Since the engine air intake wasn’t pulling from the engine compartment any more, I added 3 additional
4” air inlet hoses routed from the engine compartment up to the air inlets up on the side of the boat.

On one of those, I added an in line blower to draw air into the engine compartment to turn the air in the
engine compartment at low speeds, I ran a relay triggered off of the hourmeter to run the blowers.

The boat had 2 4” engine compartment exhaust ducts, so I was able to maintain
airflow in the engine compartment.

After the project was complete, I put a temp probe up in the plenum near the flame arrestor,
ran the boat the air temp was the same as outside temp, I put the probe in the engine compartment, it was 30* warmer as I recall….anyway, the project worked, It didn’t fade away and the hatch stayed on;)

Im not familiar with the air inlets on a 29 fountain, but where there’s a will there’s a way