I fixed it! No, it doesn't need a spring. (so ripster was wrong, then right, then wrong again
It looks like the bar wasn't quite in the grooves on the key. The problem is, getting it into the grooves is a real bastard. You can see why they moved the bar to the bottom. On the top, you have to find a way to pull the bar under the key until it goes in the grooves.
To do this, I had to find a piece of metal. I thought to myself, "Where am I going to get a piece of metal... here... in space... at this hour." I got a bobby pin. Now you'll probably ask, "What's a man doing with a bobby pin?" Well, don't ask. I bent the pin, stuck it in and shorted that thing out... I mean... pulled the bar back. Now, somebody get me McCroskey!
(if you don't know what the hell I'm talking about in the above paragraph, watch "Airplane II")
Thanks everybody for your help!