Windscreen wiper spacer 1970 (see picture)

This is a spacer x 2 on the wiper system.
A couple of questions.
Do these go on the outside of the body and do they have a  rubber between the spacer and the body , what shape is the seal??
Is the order, wiper arm (fitted to the spline) nut - steel washer- spacer (pictured)- rubber gasket- body- internal mechanism.
Were they painted from the factory, what colour should they be painted??

Thanks for the drawings.
Any ideas on the original paint colour.??

Only seen satin stainless on Capris here.
But given they are easily swappable and replaceable, maybe someone can confirm "all black" via some authoritative source (advice pls whooligan et al ??).
 
And two styles of blade frame - wire and pressed metal.
Generic Trico brand stuff.