Oh boy, I just love working on puzzles...LOL!
Okay, the hinges that hold the door ON are okay, and it's the handle thats missing. If I got this right, you have a straight piece of metal that has a little hole in it?
If this is what we are talking about, it will be simple to fix...but we need to make sure that the element is gonna work. That way you can get all the parts at the same time.
You'll need to take Smokin's advice about going to Target and buying a probe like this one. Taylor probe
Don't worry if its not the exact probe/manufactor, this is just what to look for.
Then close door and put concrete block against it to hold shut and follow Smokin's direction on running it for one hour. Don't let the probe come into contact with the shelf. I would use a small potato and run the probe through it so the end sticks out the other side, but is up off the shelf.
The point of the probe is what reads temp.
Any questions?