Joules my car doesn't have the spindle retainer nut shown in your pic. It has a spindle washer with keyway and the nut is shaped so that it looks into the spindle groove.
You have to be within a half turn on the nut so there doesn't seem to be a "perfect" number of turns to get it right. 1/2 turn one way and too tight, 1/2 turn the other way and seems loose.
I also have a left hand spindle nut on the RF and a right hand nut on the LF if that matters. Car is a 72 pre-L #3590.
Thanks,
John