Not all the A15's run the clutch fan, some come with a conventional fan. The problem with the clutch fan is that when the clutches stop working they lock up so the fan is constantly running. With the old plastic 4 blades, this wasn't a problem, but these new multibladed, metal centred things are heavy & take a lot of power to turn. Both my Navaras had the fan locked up, so i fitted electric fans. Either stick with the original one, or go for an electric fan.The stock fan doesn't take that much to
turn, my Hillclimb 1000 had a plastic fan because of the long queues going up to the start lines & i never noticed any significant loss of power.
PS the difference between the 2 styles of A series distributors is the base plate, but yours being a 120y the distributor will drop straight in.