According to KONI there is no way to get to the top of the rear shock. I'm not sure I agree. I'm pulling mine again tomorrow to run the backs up 1/2 turn. I'll see if I can identify why they had to do it this way.

 

As you can see in the picture, the top of the rear shock is completely inaccessible when installed. There is not an easy way to access the top of the shock (where the external adjuster normally is) since it is covered by support structure of the car. It takes about 45 minutes per side to remove the shock assembly,separate the shock, adjust, reassemble and reinstall. The 1/2 turn setting is a bit firmer but probably better as an all around setting.

 

What to buy hmmmmmm basics or konis with rb springs