Prop Shaft Height

[rekcuftar]

I am rigging a small runabout with with an older OMC 75. The hull is new and I was going to run the motor on a Bobs jack plate. My motor has a 20 inch mid and I wondering if I mounted the motor to the plate using the lowest set of holes possible on the motor, could I also be able to run the same motor with a 15 inch mid at some later time using the highest settings? What is the highest that I will want to be able to raise my propshaft centerline relative to the pad? Conversely, how low will I want to be able to run my prob centerline relative to the pad. Mabe the 2" on the motor would make both sub optimal?