K-member and mount ??

Hello all,

I have a 74 Duster /6 car that was already converted to V8 (318) via motor mount kit w/727 and 8.75 rear. The motor currently seems to sit a little high. Anyway, this winter I'm replacing the 318 with a fresh 340 and wondered if it would be worth swapping the k-member for a V8 member or just go with the motor mount kit that I have. Do I have anything to gain by replacing the K-member? Also, is the height thing just in my head or could there be something to that too? I ask about the height because I planned to use an Edelbrock airgap intake and I think it will add a little more height to the carb.