There are two fuse box under hood in 2003 Chevy impala.
See the diagram below
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See the diagram below
Here are the fuse block location and labels.
As for it not starting, if moving the relays around is when you noticed the problem, then you should try to get the relays back to their original locations, as much as possible.
One of the rules of troubleshooting (guideline really) is the you should only change one thing at a time and then test what happens. If you don't notice any change, the put the parts back in their original location.
Here is the label for the top fuse block.
And here is the one for the bottom fuse block.
This will help.
Thanks.
See below fuse related help solutions :----
While going in reverse mode Fuse number 27 blows on Ford Ranger?
Where is the fuse for the master power window switch located on gmc envoy?
http://technoanswers.blogspot.com/2011/07/where-is-fuse-for-master-power-window.html
http://technoanswers.blogspot.com/2011/07/where-is-fuse-for-master-power-window.html