Unlock the distributor and put the correct curve in it. Locking the timing out is wrong.
Set the initial, idle timing, at or close to 14 to 16 BTDC and total of 34 to 36 BTDC and let us know how that works for you I use the Mr. Gasket 96B springs (I hope that is the correct part number, maybe I should go look at some on the shelf, it is for GM distributors )
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)