I think a 19 is a little too much prop for that boat, but if the engine is up to snuff, it should get up on plane.
You say the Anti Ventilation Plate is within 2 inches of the Bottom of the hull. Is that, as asked above, 2 inches above or below the hull bottom, or 2 inches away from it when the engine is tilted down all the way?
As mentioned above
Compression Test
Does the Spark jump a 7/16" gap?
Fuel getting to all three carbs?
Are the carbs functioning?
That engine has a WOT range of 4500 - 5500 rpm