[Milsurplus] FRR-10 related to FRR-24 and FRR-37?

[Nick England]

The AN/FRR-24 and AN/FRR-37 are big US Navy 1950-era National HF diversity
receivers.
AN/FRR-24 is 4 racks, triple diversity and AN/FRR-37 is 3 racks, dual
diversity.
Info at http://www.virhistory.com/ham/frr24.htm

I understand the FRR-10 is related somehow, but I don't know anything about
it yet.
Does anyone out there know anything at all about the FRR-10?
I am also looking for modules or complete racks for these receivers.
Also would like to get a copy of system cabling diagram for FRR-37.

thanks,
Nick England
Chapel Hill NC