There were no gearshift or steering wheel locks on US Mopars prior to the 1970 model year, and I will be very interested and quite surprised to see any documentation of the alleged '64-5-6 column locks on the Mopars that were sent to Sweden, which were almost identical to US spec cars with the exception of the speedometer, headlamp lens-reflector units, and a few other minor details.
As for the question at hand: the differences are minor. Column to floorpan plates changed configuration from '65 to '66, the turn signal switch connector changed from '63-'64, and the style of shift lever knob changed from '65-'66.