[Johnson] Viking II PTT - Civil Defense version questions

[k2gtm at usadatanet.net]

Hi everyone,
  I'm new to the world of Johnson equipment (but I've worked with a lot of Heath
and Drake tube equipment).  I recently purchased a Viking II and the front
panel has a CD (civil defense) sticker on it.  I heard that the CD version was
supposed to have more rugged components, wider tuning capability and factory
installed PTT.  My rig doesn't have the PTT and the tuning seems to cover only
the ham bands.  The CD sticker seems to be original to the radio.
  Can someone fill me in a little more on the CD version?  I'm going through the
transmitter now and I'd like to add PTT and any other good improvements while
I'm in there.

  Thanks and 73,
  - Greg K2GTM