Should OPs be able to bypass this permission? Should owners of the vehicle be able to wrench their own vehicles. Should the wrench just not wrench any vehicle whatsoever? Need more context here to implement this.

Whats the point? No longer able to pick up vehicles? Mr. Crayfish intensifies

Just lock yo vehicle so it don't get got

OPs yes, owners no, only for operators (For when vehicles get too stuck/bugged to be moved by a tow truck)

(Even a config option would work)

My vision of that feature:
A car owner can use the wrench on their own car to change parts and so on, but should not be able to shift wrench their UNUcord and fit it in the inventory between porkchops and potatoes, tho, if being in gamemode 1: you may shift wrench only if you are owner, if you are OP, you may shift wrench any cars regardless of gamemode, owner and so on.

That sounds complicated, though not necessarily impossible. Will consider, but not right now.

Implemented in 15.10.0.