"The AN/SPG-53 was a United States Navy gun fire-control radar used in conjunction with the Mark 68 gun fire-control system...aboard Belknap-class cruisers, Mitscher-class destroyers, Forrest Sherman-class destroyers, Farragut-class destroyers, Charles F. Adams-class destroyers, Knox-class frigates as well as others."
I found a decent pic of the complete Mark 68 Director, with closer looks at the cab face here and here
Looks to me like some judicious chiseling could sculpt (a pretty decent) one out of a WWII-type (i.e., tapered-faced) Mk37!
Otherwise, I know the Airfix 600-scale Rommel is based on a Charles F. Adams class DD: perhaps it has a decent Mk68 ready-made. And again, take a look at "700-scale" parts, for possibly a Mk68 cab in 600-scale that will look light-years better than Renwal's (featureless cube of a) part, buddy.