In April 1942, the first cargo ship converted to support amphibious landings was launched at the Beaumont Shipbuilding and Drydock Company as the AK-1 Guadalupe Peak:
Hastily converted from an existing cargo ship design, the Guadalupe Peak was a less-than-ideal-conversion, but her hull was a simple design that was easily adapted to the navy's use. Similar to the US Navy's conversion of existing maritime designs, the Guadalupe Peaks would carry several thousand tons of cargo for Marine and Army landing forces in Europe, and later the Pacific.
Lightly armed in April 1942 with just 4 3"/50 dual purpose guns, later armament would include 20mm Oerlikons and 40mm Bofors as air threat increased, especially for the Pacific theater.
Thanks to Novice for his excellent C1-A cargo ship. Incidentally, C1-As were actually built in Beaumont in the Pennsylvania Shipyard.