My v8, 4.6 has a water pump that has to remove from the back side and yes I first used the special tool but this is the one that dealers are quoting $2000 to remove. I have loosened most of the bolts but still can't get enough clearance
Sounds like a Northstar.....yeah, not anything easy to do on that. My guys HATE them. Great performing engine, but EVERYTHING leaks on them, as I'm sure you've found out. Tell me what car you've got and I'll ask one of the fellas in the shop here for any tips.
I believe the Northstar motor was the first one that GM specified stop leak to be added to the cooling system. Once we realized that in the independent shop I started my career in back in the late 80's, those cars were a lot easier to deal with, because as you said "everything leaks" on that engine. 2-3 tabs of GM stopleak does wonders for them. JW