Few notes for anyone modeling BNSF and wanting to use the MTL SD40-2's which were released in BN a few months ago:

BN 6701 --> BNSF 6701
Photos on rrpicturearchives.net only show BNSF 6701 in Heritage I pretty early, no patch photos. Going back to the BN 6701 photos, it looks like this unit kept the nose stripes and high headlight to the merger. I used inspiration from patched photos of 6703 (though 6703 had a low headlight) to put small BNSF on the cab subbase. Still need to go through and paint the tread and pilot/steps black on this unit.
BN 6704 --> BNSF 6704
This unit is a little more troublesome if you're modeling modern day. It was in white face at the merger, and more recently had an engine fire... (
http://www.rrpicturearchives.net/showPicture.aspx?id=1645139 )
Little bit of paint, some decals, and an interesting unit is underway. This one looks much better than stock with the tread and pilots painted black.