So, in the process of installing my terrafirma lift the nuts for the upper rear shock mounts stripped and I am having a hell of a time finding the specs to try to replace it. It definitely seems to be an M12, but none of the thread patterns seem to work unless I am doing something wrong. Any ideas? An M12 1.25 fits on the bottom of the old shock, but when I tried to put the same pattern nut on the upper mount (since they looked the same) the nut stripped.

 

Well, not sure what it used to be, but it is an M12 1.5 now thanks to a die.

 

That is the right size.