Insulating hole in exterior wall caused by outside electrical outlet panel
 

We are remodeling a room in our house and took down some old wallpaper. When we did, we discovered a section of the exterior wall that had visible black mold on the outside surface of the drywall. I cut the wall open and the entire layer of insulation was covered in black mold. I took that out and underneath it all was this gaping hole caused by an exterior electrical outlet panel:

Attachment 65732

What is the best way to cover that up to prevent the cold air from coming in? The back of the outlet pierced a hole in the wall and I guess they did that on purpose to run the wire to the home, but the cold air mixed with the air vent to the right is the cause of the mold and made that area moist and fragile. I'd like to layer that with something before I put fresh insulation in obviously, but I don't know what material to use.

Thanks.

Post a picture of the outside something does not look right here.

Here is the front. Right next to the door to our patio.

Attachment 65762

Got a real mess there.
#1 That sidng block is only held in place with 2 nails where it needs at least 4.
Looks like someone forgot to bring there key hole saw that day and made the hole with a hammer.

Would be a whole lot better with a siding block like this so the only hole would have been one big enough for the wire.
http://www.bing.com/images/search?q=...ectedIndex=551

I'd be very surprized if that siding was even flashed correctly where it meets the deck.
If it was mine I'd be removing the siding in that area to see what's going on, cutting out that nasty Cellotex between the studs and replacing it with OSB or plywood so you would have something to attach the siding block to.
Making sure there was Tyvek on the wall.
Installing the new siding block and using window tape around it to seal it.

Well, that's definitely not the news I wanted to hear. I appreciate your expertise and advice. Do you have a general idea on how much a repair would cost? I'm guessing the deck / siding are not flashed properly either just by looking inside the wall.