Water pump removal

[JB_Fraser]

Which aspect, Allen cap bolts or pump?
For the bolts: Make sure you have Allen hex drivers for your socket wrench so you can get the required torque and leverage to get them out.
For the pump assembly:You can get a special tool (I machined my own) that is like a claw foot wrench to fit around the pump housing so you can put a long socket wrench or breaker bar on it to break it free from the engine.
There will most certainly be some corrosion helping to hold this in place and channel lock plies will not give the positive grip and leverage you are looking for.
Couple of 'whacks' with a hammer may help as well.

Cheers