Interesting, thanks. So there was some sort of interim installation - the stub of the cage mainmast was removed and the solid tower installed sometime before April 1944, with something atop it - any idea what? - and then the Mark 34 was installed in the Sept-October refit. The aft radar in the April shot looks similar to the one on the foretop, which is presumably a Mark 3. That might also explain the reference to an aft director on Maryland in the navweaps paper.