Lay out newspaper to protect the surface your are working on. Nail polish remover (acetone) removes many type finishes.
Dampen -- do not soak -- the lint-free cloth in the nail polish remover.
Rub the brass piece with the dampened cloth. (ref 1)
Make sure to cover the entire area, including any crevices.
Dampen and rub until the lacquer is dissolved.
Use new cloths as the others get dirty.
Fill one bowl with hot water.
Dampen another clean, lint-free cloth in the hot water. Again, do not soak the cloth, just dampen.
Wipe down the brass piece, removing the softened lacquer.
Use new cloths as the others get dirty.
Allow the piece to air dry completely.
Fill the second bowl with enough vinegar to cover the piece.
Make sure the piece is dry.
Saturate the paint brush with the vinegar.
Brush the entire piece, making sure to get in crevices.
Watch as the vinegar reacts with the brass, oxidizing into a faux antiqued look.