Measure your prop to pad and if it's lower that 3" you'll never get rid of the chine walk most run that boat at 2.5" under and up. If you don't learn to control the chine you'll never get to 70. After you take off if you don't trim out all the way and don't open the throttle all the way and it will be easier to drive until you can control it. That trim gauge you have will usually be reading 1/4 when the motor is trimmed out. While the boat is on the trailer trim the motor up until it clears the two trims rams then ease it down until it touches then go look at the trim gauge and see where it's setting and that will be trimmed out.