Engine block coolant drain plugs

I am trying to locate the engine block drain plugs on my 450, I think I have found the correct bolt head on my (UK) passenger side.

It is just forward of the engine mount.



However the other side looks like this, a large hex plug. It is between the oil filter and engine mount.



Is this also a coolant drain or is there another plug located elsewhere?

I've been searching back through some old pictures and found this, it looks like the drain plug is behind the engine mount on the other side. Is this correct?

Yes