The Iowa class battlships carried the Paravanes just aft of the forward 40mm gun tubs, I would say that this would have been the same if the Montana's had been built.
The Montana's design was pretty much set by late 1941 with some design work continuing into 1943, a lot of the turret components were already orderd and being made prior to the ships being cancelled, the materials that were completed were maintained as spares for the Iowa class, it was common to start the turrets prior to starting the hull.
I came upon some Montana stuff back in the 1980's when I was working in the battleship program. there were memos and sketches of the ships that more closely followed the Iowa design, remember in late 1942 the Iowas were being reconfigured in the way of the bridge design and AA fit.
The structure for the 3 quad 40 mounts that were on either side midships were anchored on the original boat crane foundation which is still mostly intact on the ships today.
This is by far the closest I have seen a model done that would have been what the Montana would have looked like when she emerged from the shipyard, I think that the 20mm galleries that were on the main deck amidships would have been removed during her post shakedown availability. Those guns would have been untenable when the 5" battery was in action.
Again...excelent rendition of the Montana
