Coolant Leak in Vee

[<PGAHOWELLS@domain.elided>]

Hi all
The coolant leak has reached epic proportions in the last two days. Pints of
coolant escaping down over the starter motor.
I presumed it was the Water Pump gland leaking, but thought I had better
check.
I examined the area of the vee with a very bright torch while the engine was
running. I can just see the water pump vent to the vee under the manifold from
top with my eye somewhere near the end of the wiper arm. 
Strange, it was dry as a bone, but the rear of the Vee was filling up with
coolant.
Looking around I can just see it dribbling from the rear of the LH cylinder
head under the manifold.
Has anyone had experience of that.
Is it a leaking head gasket, or a leaking gasket of the manifold, or is there
a hole in the head. (HaHa) I may not be laughing if the heads seized on!
All donations of related experience gratefully accepted.
Peter Howells