Did LA water pumps ever get fine thread bolts from the factory?

So double threaded studs (like a rocker arm stud?) with course into the pump flange, and fine there outward.? that sounds vaguely familiar....I'm almost recalling that on a viscous fan setup I had, but i suppose I could be remembering wrong. Probably 20 years ago.
Your memory is correct, as Del mentioned, a fine/coarse stud was often used