Ok , need to step back

Put a mild cam in the 340 and enjoy it as a cruiser.
Even if it isn’t a OE 340 car, it will command some bucks. Use the KISS method and it’ll be fine. Even if it is sporting a bunch of OE stuff
Keep the Dart to stomp *** and use the Duster to cruise.
That was my first intension when I picked up the Duster but I also have room issues . Not having a shop only a three bay garage space is tight ,it makes it hard to work. I think I need to be senceable. I know I can get more then what I paid for the Duster and its all there including new parts