what is the positioning of the brushes in a 12volt
The two grounded brushes are hooked to the brush plate just as they were in the 6-volt application. If you are not sure which brush holders they are, check them with an ohms meter. The other two insulated brushes are attached to the end of the fields. See the photo attached where I am pointing to the two ends of the copper where the insulated brushes will be crimped and soldered. The other photo with the single blade of copper coming off of the fields is where they get attached to the copper contact button.