I wish this had a presets menu so I could list multiple handling settings, drift, circuit, drag etc. how hard would this be to achieve?
except it doesnt… I change something and it does nothing to the car what so ever so not all fields are adjustable.
Well, thank you for pointing out the fields that don’t work for you 
…
But yeah I found out a little problem with vector fields - I fixed 'em in last commit (kinda strange that no one have noticed it before)
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btw. the editor also works for local vehicles, but you have to use correct handling name (its not always the same as vehicle’s spawn name)
Is there a way that this can be locked to admins?
Yup, Ive added FiveM’s permission system in the last commit. You need to have command.handling permission (or access to all commands) - you can set it in cfg via e.g. add_ace identifier.steam:0000000000000000 command.handling allow more info here
(I havent tested this commit alot, I hope I did everything right, however if I have missed something - let me know)
Script seems to not be working as intended anymore 
Was super helpful, well at least for me the values do not correspond the same out of my test city