Paul,
            You could hide/unhide columns:

Sub HideselectedCol(byval Day as string)
For i = 1 To 256
If Cells(1, i) <> Day Then Columns(i).Hidden = True
Next i
End Sub

Sub mytest
HideSelectedCol "MO"
end

Sub UnHideselectedCol()
For i = 1 To 256
If Columns(i).Hidden = True Then Columns(i).Hidden = False
Next i
End Sub

Paste this into a Standard Module:

Code assumes your first  MO is in cell C1 and rightward from there..
Also Cell A1 contains your criteria say,  WE

Sub Foo()
Range("C1").Select
Do Until ActiveCell = ""
If ActiveCell.Value <> Range("A1").Value Then
ActiveCell.EntireColumn.Hidden = True
End If
ActiveCell.Offset(0, 1).Select
Loop
End Sub