Ball Height Vs. Coupler Height

Part of the set up instructions for our BlueOx SwayPro said to adjust so that the ball is 1"-1.5" higher than the coupler (as a starter).

Give it a try and see. You may not need to buy a new shank.

The tongue weight might bring it down, I have a few different trailers of different heights and have an adjustable ball mount.Adjustable Ball Mount. There are a ton of choices but having the height option is nice.

As I recall from Equal-i-zer installation instructions, you need to get the ball down to the level of the coupler (assuming the trailer itself is leveled). Otherwise your TT is likely to be nose-high when hooked up with the bars. Especially with a 3/4 ton which will squat less than your old 1/2 ton. Nose-up trailers do not tow as well. If you try to compensate with less pressure on the bars, you will have less WD and less sway control.

your 3/4 ton will not sink down that far. so my guess would be get a new adjustable shank

You want to end up with a level trailer when hooked up and bars properly tensioned.

Have you set the trailer on the ball yet or is this the pre-check during installation?

Step 8 of the installation (trailer pitch adjustment) calls out moving the ball up if the trailer pitches down when everything is hooked up and properly tensioned... The starting point is to set the ball and coupler height aligned. Conversely, if the trailer pitches up, then lower the ball and go through everything again.

So I would go through the setup and see if it is OK in the end. But the 3/4 ton does sit higher and has stiffer springs than an F-150, so odds are you will end up with a nose-up trailer (or very lightly tensioned bars), and will need a new shank.