I used Hammerite aerosol on undercarriage parts on my Model A. I bought it locally but here's an internet link : http://www.jamestowndistributors.com/userportal/show_product.do?pid=1525&familyName=Hammerite+Rust+Cap+%22Smooth+Finish%22++spray+paint+

It's expensive but the hammered finish looks great and holds up great too.

Here's some photos from about 15 years ago, The red 4-bar, drive shaft, battery box and brake cylinder mount and pedal are Hammerite:
http://i645.photobucket.com/albums/uu176/lakeroadster/1931%20Ford%20Tudor/0601995.jpg

Here's a close up from about a month ago:
http://i645.photobucket.com/albums/uu176/lakeroadster/1931%20Ford%20Tudor/GEDC3012_zpsbc66c14d.jpg

Hope this helps. thumbs_up

In the Stovebolt Gallery ~~ "The Orange Crate" 1965 C10 SWB Step Side Build Thread

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