63 falcon ranchero

I have a 63 ranchero that was an original 260 V8 and I replaced the motor and trans with a 302/C4 combo and rebuilt the front suspension with new nos parts except for the coil springs and shocks. I bought after market springs and gas shocks. The car rides like a tank, really stiff. I would like to put back my original springs but I sold them(dumb) I looked up in my ford interchange parts book and it says that 64-65 mustang front coil springs are the same as the 63/V8 falcons. True or false? If true can you purchase original spring tension values. Can my gas shocks contribute to the stiff ride, if so what shocks should I use? Thanks, Harold Pickett