Tomorrow I'm going 'dizzy hunting' at my buddies place.He's got 18 L.C. in his back yard.Mine is a '74 with vac retard. If I'm reading all the posts right,I need a pre '68 or a '78-80 dizzy to drop right in my '74 to make it vac advance.I want to keep the smaller dist. cap,and not have to worry about the side plate. Am I correct on this? Thanks!!