Need a bolt size, please

[John Larson]

Seat belt bolts are of a universal thread size.  Any seat belt bolt of the
right configuration (shoulder, etc.) fits any car.  A safety mandate, I
believe.  Seat belt bolt holes in the earliest 356s and VWs to even have
them (even if the cars didn't have seat belts!) are the same size as the
newest cars.  Any bone yard can supply you with a bolt that will work.  The
shoulder harness bolt on my 65 911 is 8 mm, though, so it's possible that
only the floor anchor bolts were originally under the standard.  BTW, my tap
set has an 11 mm (7/16) tap of the right thread pitch.  HTH, John