No ... the original one deck higher medium AA mount between 53 and 54 mount was limited to the first few Original Closed Bridge FLETCHER units. The lowered 53-54 mount installation AND the fantail twin 40-mm mount was standard on the Revised Open Bridge FLETCHERS from the start. All of the Square-bridge FLETCHERS were completed after the elevated 20-mm gun was added. There were several different versions of this elevated centerline tub depending on which yard built the ship. Compared to the tub used on the Round-bridge units, it was more angular (see photos above).
To "convert" to the lowered position ... look at the photos I posted above ... you start by leaving off the elevated "tub" down to the 01 deckhouse and build the lowered "tub" and an elevated Mk 51 (or Mk 49) director at the forward end. There were two styles of "tubs" for the lower installation ... the "standard tear-drop" that was on all production FLETCHERS and the Mare Island Navy Yard style installed on many FLETCHERS modified or repaired at MINY. Also, the aft conn station that WAS under the elevated AA position was relocated to the fore end of the Searchlight Platform (first on the second stack and then with the addition of the waist twin 40-mm mounts, to the forward stack).
If you go back in this thread there are multiple postings of drawings and photos doing just this same thing. You can also invest ($30) in the Destroyer History Foundation " BIW FLETCHER Class Engineering Drawings" DVD ...
http://destroyerhistory.org/destroyers/store/ ...
Refer to the following pages in this thread:
Pg 16 has a close-up view of a "Standard" tub between 53 and 54 mounts.
Pg 9 and 42 have views of the MINY tub between 53 and 54 mounts.
Pg 30 has several attachments about the first Revised Open (Square) Bridge verse the Revised-Revised Open (Square) Bridge installed on FLETCHERS.
Pg 40 and 50 have views and discussion about the design/layout of the "Standard" tub between 53 and 54 mounts, along with plans of the various revised platforms for the Searchlights and waist twin 40-mm mounts directors, and the forward elevated platform for a 20-mm gun before the bridge (on the Original Closed Bridge units like the Revell kit has).
If you have not figured it out yet, the Revell 1/144 scale FLETCHER kit is very limited in what can be modeled with it "out-of-the-box" without a lot of work. I thought that Revell would come out with a whole series of FLETCHER kits to cover the gambit of variations. But, so far all they have produced are two groups of very limited kits (early FLETCHER representative of seven units and the Post-WWII Z-1 class of FLETCHERS of six units). Even at that, Revell has produced an incomplete kit ... lacking bridge equipment and even having the WRONG Mk 37 Director Mod ... they have a Taper-back Mk 37 ... only used on SIMS and BENSON-GLEAVES class units ... instead of the Square-back Mk 37 director.
This guy on another website has documented many (but not all) of the errors with the Revell kit with his build of the CHEVALIER (DD-451) ...
...
http://models.rokket.biz/index.php?topic=322.0 ...