An idea I learned from Waffle and Nopoop, I think.
Draw the panel lines 1 pixel wide on a new layer.
"Duplicate" the layer into a new layer.
Adjust the color to a contrasting color. Offset the new layer 1 pixel diagonally. This gives a 2 pixel-wide panel line made of contrasting colors. Put the darker layer on top and you don't have to repaint anything where the lines cross.
Then you can play with the opacity of each independently until you like the effect.
I put the panel lines on a layer, contrasting lines on a layer, rivets on a layer, dzus fittings on a layer, oil streaks on a layer... etc.
I don't merge anything. Blur and smudge will use all visible layers allowing you to not have to merge and still get blurring effects. Oh,yeah, I'm in PS 6.
For overall smudging and weathering the "render clouds" works well to get a variying effect, too. ( Another tip someone gave in the forums...)
Great job, so far...
