Generator production changes and service replacements - What did Hudson do

My car is a 1942 Commodore 8.

It has the original three brush generator and a two relay regulator. The charging system is not being consistent or reliable so I am working things out.

I have installed new brushers, bearing, cleaned armature. I have swapped 3 regulators (good used and one NOS) It still has problems. (possibly bad field windings - still messing with it)

In reading the Hollanders to get a list of replacement numbers for the generator and regulator, It says that Hudson used the 3 brush/2 relay set up until 1950.

There are notes however that there are 2 brush 3 relay replacement set ups that were used/recommended by Hudson as service replacements. Certainly there would be wiring changes.

Parts for the 3 brush - 2 relay are not common, but eBay has many listings for the 2 brush 3 relay set up.

Can somebody explain what was happening to the charging systems during the 40s to late 50s?