Guidance: Specific driver size for pre-AI slot rear mount screws

[whatdoido]

Are there specific sizes of drivers for rear mount pre-AI slot screws?  Richard's site suggests that the screws are not always a uniform/consistent size.

I'm trying to remove the mount of a 55mm Micro P

[pluton]

I also would like to know if there are specs for the slot screws that Nikon used in that era.  One solution that always works IF you have the patience and can sacrifice an otherwise good screwdriver: Pick a slot driver that is slightly too big, and file it down so it fits.

[Erik Lund]

I can recommend a set of Wera screwdrivers, get a set of all of the small ones, there are many more as soon as you get the mount of 

[whatdoido]

Eric isnt wrong here - the joys after I took a late MIcro Nikkor-P Auto 55m apart - interestingly, internally it looks like the PC Auto that Richard covers (3x on the helicoid key)

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