Here is the installation, service , and spec sheets for the Goodman Single Stage GMES furnace.

GOODMAN SINGLE STAGE INCOMING AND MANIFOLD PRESSURES:

Incoming Natural Gas: Minimum of 4.5" w.c. and  Maximum 10" w.c.
Incoming Propane or LP Gas: Minimum 11.0" w.c. and Maximum 13.0" w.c.

Manifold Natural Gas Pressure: 3.5" w.c.
Manifold Propane or Lp Gas Pressure: 10.0" w.c