I understand you too
but i think the low driver in the S3100 needs more room
therefore the holes in the midplate !
and the ME120HS in the S2600 is seperately

because look at the drawings
the damping material ends with the plate (S2600)

iam not shure becaus ive no orginal S2600

you are right with the Driver !
behind the Horn there is a ferrit plate
which fixating the 2426H at the cabinet and the horn adapter !
i think you must get behind the driver.... to screw it out
but there is no space ??? hmmmmm

i dont know ?
therefore i need my plate behind the cabinet ....
to screw it out ...