ProComp Preload Spacer Removal

I needs some advise from the suspension gurus. My truck has what i believe to be the 4in lift from ProComp. It has a 3in coil spacer (Above the Coil) and 1 1/4" preload spacer (In Coil).

I need to replace the front struts soon and would like to eliminate the preload spacer to improve the ride. More than likely will go with Bilstein 5100. Truck is used as daily driving and towing.

1. How much lift does the 1 1/4" preload spacer provide? I emailed ProComp and they just sent me the install instructions for the 4in kit.

2. Would using a lift spring be better than increasing preload using the adjustments on the 5100?

 

So I was able to find that I do have the 4in kit via this old post on Tundra Talk. :https://www.tundratalk.net/threads/pro-comp-4-lift-review.197225/

So since the drop bracket is 4in and the above the coil spacer is 3in, then I'm guessing the (In Coil) spacer is a 1 to 1 lift ratio.