Time for some revisions here...
First of all, I've been referring to the subject of my build as 'Powerful'. However, I recently realized that a closer translation of ‘СИЛЬНЫЙ’ is 'Strong', so that's how I'm going to refer to the subject vehicle from now on.
Next, I posted a pic on the 'Kliment Voroshilov. KV series of tanks Appreciation Society' group on Facebook, showing the casting number on the turret rear face of my build. Somebody over there posted a pic of the Parfino vehicle, showing the casting number in more detail than I'd previously been able to find, and showing my initial interpretation was incorrect.
The casting number was comprised of two parts. Above the horizontal line was a two-part number indicating the month in which the turret was cast. The Parfino vehicle carries '7-9' which indicates September (the ninth month) of 1943 (I don't know why 1943 is '7'). The lower part of the number is sequential and indicates the number of this turret in the series. The Parfino vehicle carries '360'. We don't know exactly what number 'Strong' carried so I used some modeler's license and used '350'.
As with the first attempt, I made the numbers from short lengths of 10-thou styrene rod, except for the curly '3' for which I used 10-thou phosphor bronze wire.
Another discussion on Facebook turned up some decent photos and drawings of the cupola roof, and showed some details I'd missed. I therefore went back and added rain strips to the roof over each periscope cover, as well as the little domed 'bumps' inboard of the right-hand side of each periscope cover. I'm not certain what these were for, but I'm assuming they provided clearance for the operating mechanisms that allowed the periscope covers to be opened and closed.
I used 10-thou styrene sheet for the ridges/strips, glued to the roof. After the glue had set, I filed and sanded the edges to blend them into the main portion of the roof.
The domed 'bumps' are 5-thou styrene sheet, cut out with my Waldron Punch set. I used the rounded end of a sculpting tool to 'dish' the undersides and create the domes. I then glued the pieces in place and after the glue had set, gently filed the edges to blend them in.