[VFB] Using Mallard Flank Feathers???

[Chuck Alexander]

Folks: I received some (beautiful)Gold, brown, and Olive Mallard flank feathers in my kit, but haven't had a chance to try them... I cam across this pattern http://www.flytyingforum.com/index.php?act=flyshow&s=$s&showid=1802   for a "Olive Zoo Cougar".. that used those flank feathers.. Problem with pics like some have said here before, is that pics are on two deminsions, so my question is, Do I use a matching flank feather on the opposite side of this fly (and others like it??? Or do they just have the one feather going up and over the top??? Thanks in advance, Chuck