I have a /6 auto. 70 Dart swinger that I am about to start rebuilding. It will be my primary vehicle. For now I am just rebuilding the stock type stuff with the exception of the interior and engine/trans and front brakes. I want to drop a fun to drive yet somewhat gas efficient combo in it so I was thinking the 300hp 4.7 with a manual and 3.23 gears with lsd. I will be doing as much of the work as possible with the help and guidance of my father. Here is what I have so far...

Complete and refurbished 73 V8 K-frame with new poly front end kit and refurbished steering and suspension
new Comp. Eng. 3 position shocks
rebuilt power steering box
Willwood Dyna lite Pro disc brake kit(forged calipers, Al hubs, solid/vented rotors, for power brakes)
8 3/4 housing

Does anyone know anyone that has done this swap? Nothing came up when I searched Moparts nor the internet. I am pretty determined to make it work but if there is a Magnum or LA combo that compares to the 300hp 4.7 combo in both power and efficiency, I will definitely consider it.

Thank you in advance for the help.

Jared