Nikon fe film camera shutter problem?

I have an old nikon fe and have been trying to get it working, but when I tried to take a picture the shutter was not open nor would open, I took the lense off and saw the foam arounnd the mirror had decayed and that it was sticking, I researched that could be the problem so I covered the sticky are with cello tape on the mirror and the area above (obviously not covering the mirror) then I realized there is a metal switch in the left that moves up when then mirror comes down, and the only way to keep the mirror down was to manually push this lever up, then when the lens is on you can see through, but when I press the 'take' button it goes back up but not back down.

Could anyone shed any light on what is wrong with it and whether it can be fixed?