Diff lock actuator removal
 

I've just overhauled the actuator by the right rear driveshaft, using the ninemeister kit, and had moved on to the 2nd harder to reach one under the car (I get confused as to which is the lateral and which is the longitudinal),
but I can't slide the locking bracket out. I suspect it has been sat in there for a very long time, so I've done the usual cleaning and soaking with penetrant.

However, are there any tricks that I'm missing, before I leave it until the engine/gearbox drop next winter?

If its been there for a long time, it can be difficult to remove. In my case, I used penetrating oil and taps with a rubber mallet. It took a long time to get free.

Wiggle the slave at the same time as you pull. If that doesn't work, get a flat head screw driver and tap tap tap. It'll eventually work loose. It just slips in...so once it loosens up, it'll pull right out