The easiest way IMO is to place the DWG as a drawing "File -> External Content -> Place External Content". This will not polute your AC file with a lot of layers or other parameters.
After placing select the drawing, right click and select properties, there look for "Pen Set" click on "Drawings Own Pen Set" and click "Add to Project Pen Sets"
Go to "Options -> Pen and Colors" and Select the saved pen set and edit the colors to change to black the ones you need and change the colors of the others as desired.
Go back to the drawing and select its settings again and under "Pen Sets" change from "by source" to the newly created pen set. Make sure that under "Colors" , original colors is selected.
This was the procedure before GO's was introduced.
eduardo rolón AIA NCARB
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