1975 Mercury Montego upper control arm nuts

I have everything apart and out to the powder coater as far as front suspension goes . Is there a source for new lock nuts for the upper control arm shafts , the nuts that tighten the bushings up ? 

Wondering if there is a left and right to the front upper control arms on a 75 ? Or if they are symmetrical side to side ?

I can’t see any difference in them laying them on top of each other.  Side by side    End to end 

Someone here soon will chime in say for sure. I took mine to work in about 1989 and spent an hour or two grinding all of the edges smooth, just to kill some time to make them nicer before painting them. I also installed Delrin bushings so my fuzzy memory tells me they were identical when I put them on.

 i believe they are the same IIRC if you need an A arm let me know i have a few

My simple thought process is more threads in a nut equals more clamping / holding force . Is that wrong to assume that ? Maybe they used the thinner lock nuts because the cross shaft isn’t built with enough threads to fully engage a standard lock nuts “ locking” feature . I looked at pictures I took before disassembling them and there are only about 3 threads left outside the thin nut . That may be the reason !! Going to the hardware store this afternoon with a cross shaft to see if I can find an acceptable thin lock nut ! Worst case scenario, I reuse the original ones , apply locktite , and reference how tight they are with a marking pencil and watch them over time for backing off . 

I am fortunate to have a family owned hardware store near me that has the end all , be all , of nuts  and bolts selection !! They have bolts that are 28$ a piece and everything in between ! It’s really a Disney land kinda place for a hot rodder  !!!