I just dug into the rear end of my newly acquired '13 runabout. A former owner obviously had not considered the difference. He had cotter pins for the six d.s. roller bearing studs. None ever came loose though. I pulled apart the differential today, and it still has the old style differential case with studs. Again, there were cotter pins where there should have been safety wire. Since the engine was not in the car when I purchased it, I don't know about the wishbone cap, but I'm sure he would have cotter-pinned it too! I redid the magneto a few years ago, but I don't recall what was on the magnet bolts.
A few year ago I took apart a rear end with the early style diffy case with the studs. Again, no safety wire plus NO cotter pins. In their place were bent over shingle nails! Nothing was busted but maybe it wasn't run far. Ya never know the mysteries to be found taking T stuff apart. I guess I should have kept a record of all the
"shade tree fixes" I found.
Back in the day when I could afford to be in aviation, I owned a 1947 Navion for which I had to procure a replacement engine. This was duly inspected by an FAA-certified mechanic who made the discovery that everything requiring safety-wiring on the outside of the engine had been done backwards. Having at least a lick of sense, I knew that, from that point, a complete tear-down of the engine was the only safe way to go. That's what the guys in my flying club used to refer to as "a real stiff headwind."
And yes, everything on the inside had been safety-wired backwards, too.