I'm having wierd, seemingly unrelated electrical problems with my 1998 pontiac trans sport montana

1st both the power windows on the passenger side quit working.
2nd the thermometer on the overhead started showing the wrong temp
3rd the display on the radio only works occasionally (stays blank) but the radio works fine.
4th sometimes while driving the power door locks start locking and unlocking by themselves. (may go on for 5 minutes before they stop)
5th one night the horn started honking at 3:00 am.(sporadically no set pattern or duration) Finely just pulled the horn fuse to make it stop.
6th one night a neighbor told me I left my lights on. Went to turn them off and couldn't. It was the daylight running lights that were on. Did every thing the owners manual said to do including setting the parking brake. nothing worked. you guessed it, I pulled the DRL fuse.
  I've checked all the fuses and relays in the cab and under the hood. Had the battery tested and checked the engine ground cable. All good.
  Both the fuses I pulled were from the under-hood fuse relay panel. I noticed that where the wires go into the under-hood panel it looks like the bottom of the box has come off. I don't know if its an actual sealed bottom or not, you tell me.
   Is this the problem? If it is how do I change the panel out? Do the the wires connect with plugs or is soldering required? Where do I get a replacement? What do I need to know to do the job (directions)?
  If this isn't the problem or you have other suggestions please help.  Thank You