Further to my last post, here is the information I promised.
First, from "Battleships: United States Navy Battleships, 1935-1992" by William H. Garzke, Jr. and Robert O. Dulin, Jr. there is a short paragraph stating that a plan was completed in 1955 for the Iowas to receive ten (10) twin 3in-50 cal mounts to replace all Bofors mounts on the ship. These would be controlled by six (6) additional Mark 56 directors, which could also be used with the 5in-38 cal mounts.
Secondly, from "U.S. Battleships: An Illustrated Design History" by Norman Friedman more details are available, some of which differ from the reference above. The project was a Class Improvement Plan (CIP) from 1955 that had proceeded far enough to recieve an SCB designation (SCB-74E) but was never funded. It called for all Bofors mounts (twenty (20) of the them at that time) to be replaced by sixteen (16) twin 3in-50 cal mounts, with none on turret tops and the uppermost quad Bofors positions abeam the second funnel to be left empty. They would be controlled by six (6) Mark 56 and three (3) Mark 63 directors. The Mark 56 directors would also have the ballistics for the 5in-38 call mounts so that they could control them as well.
The third reference is "US Battleships Conversion Projects 1942-1965: An Illustrated Technical Reference" By Wayne Scarpaci. It shows the author's impression of the SCB-74E conversion but it shows only twelve (12) of the sixteen (16) mounts in position. This may seem inconsistent with the Freidman reference but there are two additional pieces of information to be considered; from Friedman we know that some of the mounts were not to be shipped during peacetime (all wiring and foundations were in place for them to be shipped) and the drawing in Scarpaci indicates the year 1958. The year is of note as the CIP's most likely evolved over the period that they were maintained and, as such, some of the mounts may have been deleted as time went on until the CIP's themselves were deemed obsolete.
As you know the guns were never fitted. Two of the ships (Iowa and New Jersey) received all six (6) Mark 56 and two (2) of the three (3) Mark 63 directors. The other ships did not receive any of these directors.
Hope this helps.
Bigger Guns, MORE POWER!
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