For posterity, my ~/.kde/share/config/krandrrc contains:
[Screen_0] OutputsUnified=true UnifiedRect=0,0,800,600 UnifiedRotation=1
[Screen_0_Output_LVDS1] Active=true Rect=0,0,1024,768 RefreshRate=60.0038414001465 Rotation=1
but my LVSD laptop display reverted to (default) 1280x800 in X session restart.
For posterity, my ~/.kde/ share/config/ krandrrc contains:
[Screen_0] 0,0,800, 600
OutputsUnified=true
UnifiedRect=
UnifiedRotation=1
[Screen_ 0_Output_ LVDS1] 60.003841400146 5
Active=true
Rect=0,0,1024,768
RefreshRate=
Rotation=1
but my LVSD laptop display reverted to (default) 1280x800 in X session restart.