Belt Width

[El.Padrino]

What is the correct width for a power steering belt with original V-groove pulleys? I read from .41, .44, .47, .53 so now I am confused.

Also, the alternator belt has the same width as for the P/S?

It is a 383 without A/C.

 

[Ranger16]

'69 383 w/o A/C

Alternator - 3/8" (.375)
P/S - 1/2" (.050)

 

[El.Padrino]

'69 383 w/o A/C

Alternator - 3/8" (.375)
P/S - 1/2" (.050)

Thank you!
I am surprised that they used different widths as well as slim as .375".