Reagan picked Bush to appease the GOPe and prevent them from doing what they have been trying to do to Trump. Trump may or may not feel like giving the GOPe a peace offering.
Fences always have to be mended. Look for Trump to tap Kasich for VP. He’s a good party foot soldier and he knows everybody in Congress and how it all works. He will be valuable in helping shepherd Trump’s agenda through the legislature and he will be the tie break vote in the Senate.
Trump also needs to win OH in the general. That’s where it got stolen from Romney in 2012.