Having a hard time adjusting the rear spring pre-load.  I have the spanner wrench and the front was pretty easy but having a hard time with the rear. i cant get enough leverage to break the lock nut and its so tight i cant get a cheater in there, any tips other than having to take apart  stuff to get better access.

[2015 Z Force 800 53/Trail EPS]

I have had some in he past that I needed to first spray with some good penetrating spray like PB then tap the ring with a steel hammer on all the sides I could get to let go of the threads. Then the spanner worked fine. You can clean then back up with some braklean afterwards.