T25 Thermostat “Which way up”?

[Xenolith05]

Hi all,
I have a 1985 2.1DJ WBX. The thermostat housing is the type shown here in this Thermostat Bundle
I took the old thermostat out a while ago while doing other maintenance, and now being an idiot, I can’t remember which way it goes in with the O ring!
So I looked in the Haynes manual, the VW workshop manual (pdf online), and Heritage Car Parts, but Heritage have it the reverse way round:

Heritage (scroll down) - Heritage Top Cover
Workshop PDF / Haynes - Workshop page 19-9 (same as Haynes)

Can anyone tell me 100% which way it should be / a picture would be great if you have one!

Thanks

[silverbullet]

Stat first, O ring on top as ut seals the cover bonnet.