1. The fuel pump relay is located in the relay box under the passenger side dash. You should have a diagram on the cover of the box to identify the realys.
As for the relays on the firewall, here is a diagram that should help. (not sure what year this is from) Also, there should be a diagram on the back of the covers for the fuse boxes that show what each fuse is for.
Ahhh...the wet carpet. and yes, The rectangular box with wires and steel plate is one of the grounds. There is another on the driver'* side. When wet/corroded, these are often the culprit for many problems. Here are some pics of location, and good and bad ground Buss connectors. Dry everything up and clean up the ground busses so we can see if that helps any problems that you are having.