can the koni yellow adjust the height?

 

yes

 

Only 1/2" lower

 

The shock lowers 1/2" which is the travel length of the lower arm on the inside.
The actual drop measured from the wheel hub/wheel gap would be a little more than 1/2".
I know because I had this setup(Koni with stock springs) for a while.

Dan

 

actually a lot - just ditch the stock KONI perch and add slip-ons ala GC

 

best advice, only that would be significantly worse than stock if done without planning