Topband: 12V through coax

[tony.kaz at verizon.net]

I am making up new boxes for my Pennants. I will be switching directions
with a relay in the box besides the terminating resistor and the choke.  
My question is what are the correct values of the components for feeding the
12V? I will be  using this only on 160 and 80M.
For the coupling cap between the rig and antenna I have seen values from
.01-.1uf. For the choke I have seen values from 100 uhy - 4.7 mh. On the 12V
feed side I have seen values from .01 - .1 ufd. 
Is there a rule of thumb for the range of correct values for 80 and 160M?
Thanks
N2TK, Tony