I think the red line is around 5100, but others are telling me its around 4800 rpm

If you have a 454Mag (rectangular intake port heads), the high rpm rang is 4600 to 5000 with the rev limiter around 5200.
Shoot for 5000-5100rpm running light.

If you have a low out 454/7.4 (round intake port heads), the high rpm range is 4200 to 4600 with the rev limiter around 4800.
Shoot for 4600-4650rpm running light.

A 3 blade Merc Mirage or Miage + is likely going to be the fastest prop on your boat.
You may want to try a Merc Revolution 4 rather than the Bravo 1.

I had great results working with Brett at BBlades to get the max out of my prop...

You may also want to ask these questions in the Prop Talk Forum and The Baja Forum...

From the link he posted, probably has a 496mag =4800 limit.

How far below the bottom of your boat is the prop shaft (center)

Rule of thumb ... Deep p/s, and a 3 blade would likely be better than a 4 blade.

Yup...
The boat probably has the fastest prop on it already.
The Rev 4 may be worth a shot though...

I just ordered a 25 pitch mirage plus lab finished

dmn i got 1 extra non labbed on the floor right now cheap