Starting last Friday after noon I bought a new 4 core radiator to put in my 1991 K5 Blazer. I was going to change the water pump and fan clutch, but I was told that they were both fine. The removal for the old radiator was real easy, took longer to get it from the shop then it did to take it out. The only tricky part was the fan shroud. I did pull it by removing all the bolts that hold the fan to the clutch fan (most likely there was a better way to do it) this gave me the room that I needed. The 4 core is about 1 inch deeper then the 3 core that was in my truck so was told that I would have to cut the insulators (rubber feet) and bent the mounting brackets just a bit, however that was not the case. First the mounting brackets would not be long enough even if I bent the he!! Out of them, the insulators would no work at all and the fill hole was to far to the right, so that the left bracket would go back on. Found all this out after I had pulled that old radiator. SOAB!!! So I called the place that I got the radiator (about 2 miles away) and told then that there was no way that this was going to work, a different guy that worked there told me “Oh it will work just fine!!”, till I told till I told him about the fill cap. He looked at one there and told me “Oh, you are right.” The shop closed at 4:30 was not open on Sat and I had no radiator on my truck. They would not come to my house get the one that would not fit and would not drop off one that would fit, but they do deliver. So I called a friend he came over and we took it back, stop at different shop got some coolant and a new drive belt and put the other 3 core radiator, the new drive belt in and filled it up. GOOD TO GO!!! When I was working in the radiator I was looking at the tranny lines that inter the radiator and was tubing and the other was a hose?!? I looked closer and notice that the hose went under the frame and to a tranny cooler that I did not know was on the truck. WOW!!! I was going to put one on some day and now I do not have to!!! COOL. All and all the job was real easy, even for a computer geek, from Johnson Country Kansas!!