Therefore, you should not attempt to locate and replace this fuse yourself unless you have experience working on car electrical systems. Improperly working on the fuel system can be dangerous due to the flammability of fuel.
Instead of trying to find the fuse, the best course of action if you suspect a fuel pump issue is to take your Mustang to a qualified mechanic. They have the tools, experience, and safety equipment to diagnose and repair the problem correctly.