Just playing around a bit, and thought I might try and update the Jupiter as she would have looked in 1941. I removed the 4 x 5.5", 4 x 4"HA, and 4 x 2 Pdr's; replacing them with 8 x 4.5"/45 (4 x 2), 14 x 40mm (7 x 2), and 40 x 20mm (20 x 2). I also replaced the main directors, added 4 Mk.51 AA directors, gave her a new catapult and floatplane, and added some early radar to the masts.
Hopefully it looks something like what a late 20's cruiser updated in 1940-41 might look like.
the original 1927 version for comparison