2012 Phazer Rear pivot arm is stuck

[Kips]

Hey,
I have a stuck rear pivot arm (phazer 2012 gt) How are you getting these off? it is a brute force or some kind of puller? thanks

 

[74Nitro]

Two arm puller?
Air hammer from behind?
Tap a slot screwdriver into the slot opening right beside the splines to open it up some more?

 

[YukonMP]

Maybe a bit obvious but soak the hell out of it with WD40 or something else along those lines.