Front diff actuator won't come loose

[Osteoblast]

Hi,

I'm trying to check the front diff actuator on a '97 Tahoe.
One step of narrowing down 4WD trouble...

The actuator seems to be glued to the diff. It's all plastics and I can't get a firm grip with a plier.
I fear that I will crack it before it comes loose.

Any hints?

 

[Supercharged111]

The actuator screws in. If it's the later style you can hear it stroke in and out.

 

[Osteoblast]

still would be nice if it comes loose somehow