All, just a quick update.. After shipping various parts back and forth to NH I think I finally got the correct water pump, backer plates, etc. I found myself with about an hour today (my 4-year old actually took a nap for the first time in 2 years) so I dug into it a little bit. I emptied the rad and took the hoses off top and bottom and took the Tstat back out. I was looking to signs of goop in the block so I stuck a rag in the hole where the Tstat goes to see how much crud came back out. I got a fair bit of rust-brown goopy sediment. Not good.. I am going to flush the block and see if I can get some of that crud out. I took the old water pump off. The internals where covered with greenish brown sediment but worked just fine (see pics). The old pump and backer plate were all glued together with red gasket cement which made disassembly a pain. Is this cement necessary?
The old pump was definitely the long shaft 11-bolt as you can see in the picture with the old (blue) and new (black) side-by-side. I wont know if the pulley alignment will be right on until I put everything back together (likely next weekend) but I expect that alignment will be improved. I will take more pics after I get everything back together and get the mess cleaned up! I was very careful to drain the radiator into a bucket but didn’t think to have a bucket under the water pump when I took it off.. Splat! I am definitely going to replace the fan with the correct one since I have it all apart. I doubt I will be able to get the whole assembly back in though as the old one with the little fan was a bear to get out around the shroud. I guess I will have to take that off too..