I agree with Jerry. Trouble shoot, don't just change parts. That's easier for me to say than do. I lost my shop manuel and the old time mechanics that used to guide me and advise me through problems like this a long time ago are all gone. I come here for help now.
I put in a rebuilt distributor in my truck because I could wiggle the shaft side to side and I knew the bearings/bushings were worn out which would cause the point gap to be off. That helped with the problem somewhat.
Jacques

Union, Justice and Confidence