Headlamp panel screw, Lucas headlight ea 3/16inch Whitworth

Headlamp / headlight panel screw, domed head slotted, 3/16INCH wHITWORTH 24TPI  x 3/8inch.  Early headlighs MU and DU series have the 3BA screw. The later series with the thread insert have either 3BA OR 3/6 inch Whitworth and if no thread insert they used self tapping screws.
Original Lucas number:
106491 - screw