Generator pulley diameter

Im inquiring about the diameter for a generator pulley on a 62 series 1 3.8. Have a friend who has several lucas pulleys but not sure of the right diameter.
The generator is the LAST mechanical part I have to install. Another v/8 conversion returned to a period correct drive train. Thanks DJ

I have my 1963 generator in storage. If you don’t get a good answer before I am dressed and out the door, I can pull it down from the attic and measure mine for you.

DJ,
Off my 63 fhc 3.8 double-v type pulley. The outside diameter is 3 5/32 inch, the bottom of the groove is approx 2 1/2 inch
Cheers Jim