To get your 871 you multiplied 780 X 11.7 = 91. Then added it to your 780. Or maybe just multiplied 780 by 1.117 and got 871. But you should actually divide 780 by .883. If your net loss was 15% you would divide by .85. Not much difference, but the difference is in your favor. 585 /.883 is 662...
Here is a few pics of a friends car I took today. It's not a Cobra, but it's something you don't see everyday. I'm sure it's not everyone's cup of tea, but it's a nice car and thought some of you might enjoy them.