You failed to mention the year and make of your Ampico.  Every year
that Ampicos were manufactured, Ampico made a few changes including
removal or a slight difference in design of parts.  My own Ampico has
no expression cutoff block and no primary valves.

I am not sure what you mean by "crash pneumatics".  Some late Ampico
units deleted the subdued pneumatics, some spinets deleted the
reservoirs, some very late models deleted one of the crescendo
pneumatics, and some have completely different or missing amplifier
devices.  I think Ampico may have decided that you better play Ampico
rolls only, or suffer the consequences!

The problem I see with no cutout block is the absence of small
filtering screens which prevent the expression units from collecting
paper and dust from the rolls.  If one thinks about that, once the
filtering screens are filled with dust, how can the dust be removed
when the leather pouch closes it off when trying to use a tracker bar
pump?  Without a cutout block, if one is diligent about using the
tracker bar pump this will not become a serious problem.

Some tell me that the absence of an expression cutout block solves
a lot of problems with leakage and is advantageous.  I suppose that
less parts means less parts to produce problems.

In any event, you have come to the right place for guidance in your
restoration.

Bruce Clark