Should it just pull out? cos it wouldnt move at all?

they are a good fit so often tight ,apart from been glued by gasket or sealer

Sometimes the beating retaining ring (between the pto plate and the transfer box casing) has a seperate screw securing it. It may just be stuck on with gasket.

Clean the face you can see to check for a screw, if there isn't one a few gentle taps with a rubber mallet might loosen it a touch.

Mine was stuck on with rtv sealant and needed prising off.

Once that's done the bearing and gears should eventually wiggle out

Ed