Rookie coil over questions

[Northern Goat]

I am in the process of trying to set the expected ride height of my chassis and will be using steel tubing in place of the coil over to mimic the final ride height during my build.

I emailed Strange to determine what the final ride height of the single adjustable coil overs would be and received the following response:

The shock with the extended length of 17” will have a ride height between 13.875” and 14.50”. The shock with the extended length of 15” will have a ride height between 12.625” and 13.250”.

My questions seem dumb, but

- why are the ride heights of the two sets of shocks different (almost 1" difference between the midpoints of both), is this typical?
- should I assume that the longer shocks are for the front as that is where most of the weight would be?
- should I pick the mid-point in the ranges given as my preliminary ride height?