I changed my leaky water pump yesterday with no major problems. It took me a good part of the day, around 6 hours, at my own pace, including liquid and food consumption, to complete the job.
I did get the snap-on FLXM-13 tool. I was amazed that this thin, long and fragil looking tool did not "snap" when turning the 3 VERY tight bolts. I know there are some people that did not get this tool and succesfully completed this task. However, since my tool collection is not as extensive as I would like it to be, I decided to buy the snap-on.
Bottom line, I recommend that if you don't have many tools and you decided to change the water pump in your vehicle, buy this tool! It is fairly expensive at $50, as most of the snap-on tools are but, you will glad you did after you are done.

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J.H.
'86 300E