Any information about a signal corp K-18 radio truck

My question to the knowledgeable members here:

I am rebuilding a 1941 GMC WW2 k-18 communications truck that housed the scr-197 radio systems and do not have the k-19 trailer that is non-existant for this unit being complete.

Any one near - around - work in one of these units I would be totally honored to hear from you. It is being rebuilt so it can be displayed so folks can touch and feel a part of this history. It is not being restored so it can sit as a showroom quality museum piece.

We know they were on Wake Island and crew sent from Hickam Field to man it - even though they did not know where Wake Island was located (they voluntered for $4 extra a month). We know they were in New Guinea and possibly Australia as well.

I will try to post a pre and post pic of where I am at now on it.
Thanks for the outstanding site and hopefully just one of you can help.