Hey Mike,
I'd go with 'yer standard interior green on this one.
Here's some links to interesting B-26 sites. Not all of them are good for modeling reference, but you may find them enjoyable nonetheless.
http://www.b-26marauderarchive.org/MHSarc.htm
http://home.online.no/~alfjoha/B-26_Photoalbum.htm
http://pages.zdnet.com/vancell/b26tailgunner/index.html
http://www.lookamerica.com/
http://www.sound.net/~bgriner/
http://b26marauder.com/b26/b266.html
http://www.mapsairmuseum.org/marauder.htm
http://www.warbirdsresourcegroup.org/URG/b26marauder.html
http://www.nasm.edu/nasm/aero/aircraft/martin_b26.htm
http://users.visi.net/~motox/index.html
http://www.lswilson.ca/page8.htm
http://www.chez.com/eternalflight/marauder.html
The last site has some pretty nice shots of a French Marauder undergoing restoration. The second last link hasn't any real value to the modeler, but is a very thought provoking site.
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