Gotta love those wet valve cover bolts on the Chrysler, At least there is a wide variety of stock covers, That area you are working in -steering box,T-bar,starter,ex man, on a 57-58 Ply with a Hemi is one of the worst. Always seemed there was an inordinate amount of maint. issues/grief in that cubic foot, 4 bolt manifolds exacerbated it.