Actually Fel Pro as well as Mopar shop manuals list '59 and early ,60 413 engines with a 4 bolt pattern for valve covers. The rest ar the same as all the other 60's on big blocks. Ray ----- Original Message ----- From: "mike sutton" <mikanlin62@xxxxxxxxxx> To: <mailing-list@xxxxxxxxxxxxxxxx> Sent: Thursday, October 23, 2003 9:00 PM Subject: Re: IML: valve cover gasket holes > 59-65 Chrysler big block engines ( 361-383-413 ) used the 4 bolt valve > cover. The catch to this is that the cylinder heads themselves will > physically interchange from any 361-383-400-413-426W- and 440, so intake > manifold gasket and port issues not withstanding, any year can have 4 or 6 > bolt covers. > > Mikey > 62 Crown Coupe > > >