Well, tonight, tired of my "Mutenbacker" I said is time to operate again, so I put on my Dr. Rickenbackerstein" outfit and started to operate. This was like follows:
I just took the piece I bought and cut out the mute foam and glued onto the original, solded again the ground wire (this original piece has the right hole to do it, the other piece didn't) to the piece and everything worked out again. The problem was that the new piece (from a new tailpiece I'll never use) was slightly bigger than the original and didn't fit in its place so when I tried to unscrew the bolts, they got loose and the strings remained muted.
Anyway, thanks a lot Ted and Ben, you got me on the right track, 'cause although I knew the springs were there I started paying special attention to the way the piece behaved on the tailpiece. Good Guys
