Bit of investigation following last nights late panic.
None of this is actually mentioned in the SRAM service document.
The jockey wheels are marked U (upper) and L (lower).
The narrow jockey wheel is marked U only.
The wide narrow jockey wheel is marked U on one side and L on the other side. Can be used in upper or lower positions.
So to use this in the lower position, L should be read from the outside (right hand side). The wide is then ‘pointing forwards’ to unload the chain.
The sealed bearings have washers with a spigot that fit over and the pivot bolt passes through to fix the two arm pieces together.
The lower spigot washers are the same.
The upper spigot washers are different. The right side is the same as the lower, but the left side has a larger inside diameter. This sits over the raised thread in the left side arm piece.
Bearings washed out and re-packed with fresh grease.
Chain to wash and re-lube next. Will use hot chain wax in a tin. (Found a tin in the motorbike stuff).
Hope this helps someone.