SRPA file LDP578932HS shows a blueprint of a "Gun Tower Exterior Detail Assembly".
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WAR DEPT. GUN TOWER EXTERIOR DETAIL ASSEMBLY
ARLINGTON JUNCTION CONSTRUCTION WICHITA TOWER
APPROVED: 8/25/49 APPROVER:(sig "KYP")
DOC NO.: LDP578932HS
CRO 8/22/49 REV. A
NEW MATERIAL CERTIFICATION FROM SRPA WAIVED.