Several years ago, when I had by 520" stroker built there were issues with the 440 source aluminum water pump housings having poor flow from poor internal casting.
Therefore I put a Mopar performance aluminum housing on the 520" and I had a major problem with it this summer. Aluminum particles from inside of the housing could be seen floating in the coolant and had clogged up my radiator. Also, a pinhole developed from the inside out in the recessed area on the driver's side of the pump between two of the bolt holes. I replaced my aluminum housing with a good cast iron factory part.
Some of the reproduction corbin style clamps do not have the strength that the factor ones did. I traveled an hour to a car show years ago and after sitting for a little while, the pressure blew the upper radiator hose off of the thermostat housing. My two cents is to use a good quality screw clamp or use two of them. Buy black ones or paint them so that they don't stick out as being incorrect if you are trying to have the engine look factory correct.
If you don't have a set of corbin clamp pliers, get them. Hey have recessed ends to fit over the ends of the clamp and the ends of the pliers turn so that you can get on the clamp from various angles. I think that I got mine from Eastwood but it was a long time ago.
Good luck.