The substitution of 0ba and m6 is not a ” bodge” in a low torque situation. This substitution, along with using a bolt or nut with 1 or 2tpi difference has been taught in our TAFE colleges as suitable practice for low torque situations that are subject to vibration for over 50 years...….. David
So they recommend using a mis-matched thread as a 'shakeproof' fix . . interesting.
The crunch question for me is - can they be unscrewed and re-used or is this a 'one-time' fix ??
We've had the same issue with 1/4" BSF and 1/4" BSCY nuts & bolts. people think they are the same (and they can be forced to mate) but they are not - BSF having 55 deg and BSCY having 60 deg thread angles.
Personally, I'd go for thread-locker rather than a thread mis-match but I'm just an amateur.
My avatar shows the late Len Rich in 1970 with the bike I now have - a 1958 Ariel VH