The 78 rpm issue was simply alignment of the idler pulley moved down a bit by moving washers from the bottom of the idler to the top just under the c-clips. The Motorola changer is done as it works fully automatic on 78s, 45s and 33s
Now I have almost the exact same model but from the 1962 Philco. After removing, cleaning, aligning and lubing the motor/speed change mechanism, it works OK also. The issue from the beginning on this changer is:
When the stylus sets down on a record to play it, the unit switches off.