Heat Control Valve
 

Hi Guys
Re. 1963 Series 62 Convertible
Can anyone help me please. I recently had an exhaust blow at the exhaust manifold to Cylinder head joint on the rear-most cylinder of the Left hand block. Due to its inaccesability, and the fact I don't think its been removed before, I decided to go for the removal of the Cylinder head complete with Exhaust manifold.
Have since managed to remove all bolts (one sheared off, but effected a good removal of remainnig stud) I am now ready to re-build, however when I dismantled the exhaust pipe from the manifold I did not take enough care to note which way around the 'Heat Control Valve' was fitted. Also believed the Shop Manual would show me, unfortunately it only refers to this piece and states that it should be replaced with the flange marked 'TOP' nearest the manifold. However, my unit does not seem to have this marking, and there are no photo's.
I have looked at the mating faces and there are obviously four different ways of re-assembling, altough one way would bind on the manifold itself, but which of the other three is it?
Does the valve open with the flow of the exhaust at all times, or does it operate via the spring, against the flow?
Any help would be appreciated, as I don't want to put it back the wrong way around and do any damage.
Do have photo's if that's any help?
Best wishes
Baz