Mechanical keyboard help needed.

[JWBarlow]

I've decided to fix the keyboard to my ARP 2600 which has had a "sticky" high
Eb for the past five or so years; at this point it will not return, but must
be pulled back up. I have been in the keyboard a few times (for electronic
repair) but always decided to leave this mechanical problem alone since it
looked like it would require bending some rather breakable (pot?) metal which
secures the key in place. I now have concluded that it is worth the risk in
order to fix it. The keyboard is a 3604-P (monophonic; it has those cheesy
accordion type keys). Any and all help, and online references greatly
appreciated. 

Many Thanks
John Barlow