Without reading all 3 pages, not sure if the water pump ever came up in the discussion.
What water pumps is Blueprint uses on their motors ?
Notice the numbers of vanes.
Neither of the two pumps pictured are high flow pumps.
If you are going to underdrive the water pump (bad idea) then you need 8 find. If you are going to overdrive the pump (the right way to do it) you can use 6 fins.
The number of fins is less important when the pup speed is correct and the fins are closed off with a plate OR you mill the timing cover until the fins just touch the cover and then use the gasket to set the clearance between the fins and the cover.
