Relative resistance of the wiper linkage

Yep, looks like the washers are still there. A wire wheel might make them disappear. They aint much. There is a swedged collar on that end too and we wont muck with it.
If the pivots were still in the car I would start with mark the bottom of the pivot housing so they could be reinstalled rotated 180 degrees.
After removing from car...

Grind most of the mushroomed end off the bottom. Place the flat metal arm between your vise jaws and drive the pin out with a small punch. Collect the fiber washer that couldn't be seen before and keep it for reuse.
Next take the arm back to the grinder the same side as before to remove approx 1/32 inch of its thickness at the pin hole area.
Remove the pins from the pivot housings and collect flat, wavy, and fiber washers to be reinstalled in the same order. Now the housings can be flushed and the pins can be cleaned.
Reassembly in later post