[Milsurplus] AN/CRC-7 SAR radio

[Military1944 at aol.com]

AN/CRC-7 SAR radio
 
Anyone know how to get inside on of these?
I don't want to go forcing things and break something. 
Obviously the bottom unscrews to insert batteries. I can see  two screws 
down inside the battery compartment which might start in disassembly  process.
It looks like to top of the tube either unscrews or is  soldered to the 
middle bit. 
 
so, if anyone has the access code I'd be obliged. 
 
cheers, Ben G4BXD
pic of CRC-7 at:  _www.qsl.net/g4bxd/usa.htm_ 
(http://www.qsl.net/g4bxd/usa.htm)