You can get brush strokes with any paint using a "dry brush" effect. Just don't load the brush with much paint, and dab it off the brush with a cloth before you apply it. The paint will be about dry by the time it hits the body and it won't have time to flow out. I wouldn't mess with the mix of the paint or it won't cure right.

Check out model railroader tech tips for good brush and antiquing effects, they have been doing it for years and it works on full scale stuff too.

Paint & Body Shop moderator
A lone amateur built the Ark. A large group of professionals built the Titanic.