It's great to hear about a young couple restoring an older B body. Its a great story of years to come. Keep on trucking. I have several 71-74 chargers, a 75 Cordoba and a 78 Magnum. The magnum is my primary objective at this time. If you have a 91/4 rear end in your Cordoba, pull the gears from a truck/Ram Charger to upgrade to 3.55. Alburn posi units are common for the 91/4. - - - Updated - - - Regarding K-frame. Engine brackets are set back on frame. Consider relocating. K-frame on all b-body 400 from 73-78 will work.