That clutch will fit your 6 bolt fan, which is useless. I used the 2839 clutch and Kennedy 20" steel fan. That worked well for me. If you want to upgrade the pump cheap-- look here...
You may have issues with the number of splines that are on the input shaft that goes in the tranny and the output shaft for the front drive shaft. They may not match..
I had to open this thread as I was looking around and found this...
https://ssl.zoovy.com/expeditionimports/c=PRRmweQYMpoAm99s2V5CBUgtp/s=expedition-imports.com/product/251-590/251-590---AC-Delco-Waterpump-251-590---GM-88894036---65-Diesels.html
I can't afford the spin on...
I think that is just light being reflected that makes it look like heat stress. Like a prism. This is a somewhat common problem on these engines, although that may be overstating that fact a little.
Did you pressure test the cooling system with the glows out? If there is a internal leak (hd gasket) it will go into the chamber. Then crank and see if it pees.
Sounds like coolant in the combustion chamber. Starting with a punch? I hope it was not hydrostatic lock. Steaming does not sound good either. You know what you gotta do... Why did you replace head gaskets?
This ground thing everyone talks about is important. I have gone to the trouble of adding more ground wires for peace of mind. I went through the IP merry go round when it was replaced (3 times) by the dealer under warranty:skep:. Lucky me. The pump on it now has 70,000 miles on it and is OK...