@bosswrench posted:FWIW, I'm still using an ancient Weiand aluminum water pump (half the weight of an iron stocker) that I bought in the early '80s. I cracked and TIG-welded it, modified it with an impeller backplate (made no difference in cooling), and it's still on the 351-C! But I really look it over for leaks before driving any distance. Some speed parts were well made back then.
I haven't had the cover off in awhile. Mine is the Wieand pump and as I remember it, it only needs the shaft shortened.
I'd work on this now but it is the same issue as before. I don't want to drain the system and rebleed the thing again.