I am trying to change my water pump in my 4.3 86 chevy caprice and need instructions, a manual, copy of diagram, something PLEASE HELP!!! You can E-Mail me yourgirl_75@yahoo.com THANK YOU!!!!!

Try the link listed below:
http://www.autozone.com/servlet/UiBroker?ForwardPage=/az/cds/en_us/0900823d/80/1a/c5/13/0900823d801ac513.jsp
If that does not work, go to Autozone.com, go to the link that says repair info, and click on the link that says vehicle repair guides. Unfortunately, they only have guides for 1990 caprice and later, but the one for the 1990 should work for you.

Another way to get the information you need is to buy a copy of the Haynes Repair Manual for Chevrolet Full Size Models: 1960-1990, or any similar materials.

Hope this helps

Chilton's also has a publication for 1979-89 Chevy full size cars. pn# 8531

I've always found Chilton's to be more detailed than Haynes....