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How to install a Battery & Master Brake Cylinder Cover Kit on your 2005-2009 Mustang

Installation Time

15 minutes

American Muscle
Shop Parts in this Guide


*Important* Please read!

** Read entire instructions before attempting to install this product. Failure to do so could result in damage to the product which could void the warranty. **

1. Begin by identifying “Battery” cover and “Brake Cyl.” Cover as indicated by the lettering on the underside of each cover.

2. Notice that each cover has two holes to retain the cover at the front edge of the cowl above the firewall, using the existing plastic trim fasteners which fasten the cowl (plastic) to the firewall (sheet metal). Also notice that each cover has an undercut “fender tab” which is made to interlock on to the sheet metal flange of the inner fender.

3. Start your installation by locating the two wiring loom clips pushed through the sheet metal brackets toward the center of the firewall just under the front edge of the cowl. Using your fingers or pliers, gently bend the sheet metal brackets down in front slightly until the tip of the white barbed loom clip is below the level of the cowl, so as not to interfere with the fit of the new covers.

4. Remove the plastic trim fasteners with a Phillips screw driver (two fasteners for each cover).

5. Place one cover in place on the cowl flange and carefully move the interlocking “fender” tab into position before inserting the trim fasteners.

6. Carefully align the two holes in the cover with the ¼” holes in the sheet metal firewall flange. Insert the two trim fasteners and while holding the cover down securely, install the trim fastener screws and tighten, making sure not to over tighten and strip the threads.

7. Repeat this procedure on the other side.

8. Locate the windshield washer hose, on the passenger side of the underhood, where it extends out from between the hood and the hood insulation panel. Notice that the insulation panel protrudes outward in a small area around the washer hose. Using a pair of heavy duty scissors or snips, trim the insulation around the wiper hose to remove the protrusion so that it does not contact the Battery Cover.

Congratulations your installation is complete!

​If you ever need to take the covers off, just reverse the previous steps, using care not to damage the trim fasteners. Additional trim fasteners are supplied but may not be needed. Keep them handy in case you damage or lose one, as they are quite expensive if you have to purchase them from Ford.

If any you have any questions or need assistance, please call our toll free number (888) 225-7669 8:00 a.m. – 4:30 p.m. Fri-7:00 a.m.-3:30 p.m. PST and ask for Tech help. 

This guide applies to Vehicle years: 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014 and Submodels: Boss 302, V6, Bullitt, GT, GT500