We covered this end about a year ago.....
[
ngdiscussion.net] for pictures on the D&RGW that don't show anything more....
There were these, nothing else shows up in the Standard Plans.
[
www.drgw.net]
Of course the C&S lines (predecessors) were way more sophisticated....
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c-sng-discussion-forum.41377.n7.nabble.com]