To answer Tony Pignaloni's question in the 090331 MMD, according to my
notes, for the Ampico A Grand, the span of the play-reroll pneumatic(s)
should be 4 5/8".  The two outer boards are spaced apart on top and
bottom by a pair of metal plates in the rear which provide pivot holes
for the center board and by large wire staples in the front.  Assuming
that you have these parts, they control the width of the assembly and
define the span.

Hope this helps,
Pat DeWitt