Yeah, the A body Mopars are legit. My Duster started with 318/518/7.25. Went to the 408/727/8.75, wasted 3 trans, 2 driveshafts and 4 rears before finally getting the right combo. Semi 4-link on Hemi spring packs, mini tubbed with the narrowed 8.75 with 4.30s and posi on 1350 u-joints. I swapped the front to 5 on 4.5 and big disc brakes, rear had a Ford disc brake setup, electric pump for the brakes, braided lines all 4 corners. Ultimate Convertor Concepts 2750 stall, custom drive shaft, 1 7/8 primary to 3” ceramic coated headers, 3” dual all the way back with Flowmasters. Digital dash insert, MSD Digital 6 ignition, trans cooler. Integrated cage with 5 points and a 20 gal cell in the trunk.
The wife used to drive it over to the Commissary on Parris Island to get groceries; pack them around the fuel cell in the trunk. Windows down, blond hair blowing out the window put-puting along on PI. That motor wouldn’t idle below 1,100 rpm, big fat lopey bastad, so just idling along at 20mph it sounded like a nasty big block drag car. I miss those days.