This is the exhaust manifold stud that retains the manifold to the block.  The washers are X4404Z and the brass nuts are EW1833 that fit onto these studs Note: 6 studs per manifold (Sold...

This is the long head stud (3/8" x 4-7/16") for all of the 4.5 litre engines. Note: There are 9 studs per engine (Sold Each)  1952-1955  4.5 Litre Engine Only