Thanks for your replies gentlemen. What I'm looking for is a little different though. I don't want to revert layers to what they used to be or match the XREF layers to the current drawings layers. I want the layers in my XREF to match the layers of a 3rd drawing.
For example,
Let's say I have a drawing named "06-10-GRADE.dwg" which references the following:
P-Base.dwg
P-Topo.dwg
X-Base.dwg
X-Topo.dwg
06-10-GRADE.dwg has all my layout tabs for sheets 06-10 with viewports oriented properly and matchlines drawn in, North arrows, grid ticks, etc....
Now......at the end of my plan I need to have landscaping sheets. This drawing will need all the same viewports, border, etc as the grading plan so I start by doing a save as of "06-10-GRADE.dwg".
On this plan we shade back all of the proposed(P-Topo.dwg, P-Base.dwg) layers. I don't make them all the same color because I don't want them to all be the same line weight/color. So.....I change each layer individually to a different color.
What I was thinking was, if I could create a blank drawing with all the layers in P-Topo.dwg and P-Base.dwg but have the colors changed to the way I want to show them in the landscaping sheets and call it "Landscape Layers.dwg", then maybe there would be a way to alter XREF layers in my save as drawing to match these new layers?