Quoted from lb1:This assembly looks nothing like what's in the manual
This (in the OPs picture) is the new stern autofire assembly. When they switched the backbox for the next runs of Metallica they added the newly designed autofire assembly also as it is more reliable. Held in basically the same way as pop bumper assemblies. Twist shank screws through top of playfield with lock nuts on bottom, and a few normal wood screws.
Seems as if the lock nuts might have been tightened too hard at the factory and the screws finally snapped from the stress.
Birmingham, AL
