This article has excellent photos of USS St. LOUIS (CL-49), dated June 1941, of her upgrade installation at MINY of King Board ADI Upgrades. The same upgrades were applied to USS HELENA (CL-50) during her 14 July-16 September 1941, yard period at MINY. What I didn't know, was where the eight 50-cal MG's on USS HELENA and St LOUIS were located. The quad 1.1-in mounts replaced the originally installed 50-cal MG's mounted in those locations. The removed eight 50-cal MG's were then mounted on three-wheeled portable dollies that could be wheeled to their designated "lockdown" positions (sixteen options) on the main deck and back to their stowage locations.
This 24-page article includes more info on the upgrades done to these two cruisers during WWII as well.
If more information is desired, the article is available in the stated issue. You could become an INRO member and request this back issue or order the single issue.
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