Thank you for your comments.   I think I found a work-a-round.  I installed the .tiff file plotter into AutoCAD LT.  Then printed each page from CAD & it created a tiff file that I imported back into CAD; these .tiff files were able to adjust the color by the layer and so on.  Quite a few steps to take on but the end result was what I needed.  Thanks all!

I’ve played around with converting tiff files to make them 2 bit color.  It does allow me to change the imported tiff to the color of that layer.  However, when converting the tiff I lose a lot of the line work on the sheet.  The Plan sheets I’m working with show existing features in a lighter gray color (proposed features are in black).  When I convert the tiff I can’t see any of the existing features because they are too light or non-existent at that point.  Is there any solution in between?

These files are black and white. I place them on a layer with a light gray color so my line work is darker when I print it.  So you're saying I need to convert these files in some way?

Why is it that when I import TIFF files into AutoCAD LT sometimes I can change the color of the file and sometimes I can't?  I download a set of drawings from a website for my projects & every once in a while I can't change the drawing to a lighter color so that the line work I'm adding stands out more.  I'm importing the files into paperspace if that makes any difference.