powersteering triple pully on crank

[sie1970]

I'm presently rebuilding my late 1.9 DG engine and when i removed the pulley there was a strange o ring and thrower washer behind it.The o ring didn't come in the rebuild kit, think its 36x4 but i now can't remember which way round it went on the crankshaft, thrower or o ring first.

Any help will be much appreciated