I recomend you get a set of the Jim Osborn produced Mustang Assembly Manuals for your year car. Available for 1965 are: Body; Interior; Electrical; Engine: plus the 64 Weld/Sealant and Chassis manuals. To further decypher the Assembly Manuals you should get the AMK Products Guide to Ford Fasteners 1955-73. They are about 90-95 pct accurate, which is better than nothing.
Jim