Hi Carl,
I like your set up, did it come with the breaker interlock or was it something you added to thei panel to make it into a transfer panel?
I noticed in your GE main panel there is a cutlerhammer BR style breaker & a siemens breaker, & in the transfer paner there are some square d homeline breakers, I have had building inspectors & home inspectors reject panel installations for this, unless you can show them on the breaker where it says they are allowed to be used in these panels. normally they like to see GE breakers in GE panels & siemens breakers in siemens panels.
Are the pictures of your listeroid old? i didn't see your natural gas supplemental fuel system on these pictures.
Scott R.