I just got the solution from a small hardware store in Purcellville, VA. (Nichol's) An old time hardware store like I have not seen in decades I had purchased some key blanks on ebay, and took them to the store to ask if they could cut them for me. While talking about my bike, I mentioned the differences between the gas cap and the ignition key... he advised me that the key blank may be double cut with teeth on both sides, but that the lock cylinder only used one side of the key, and since it was symetrical, it didn't matter which way I inserted the key it would work...
but IF I wanted to have one key for both gas cap and ignition it was not a problem! He would just take one of my blanks and cut the ignition key notches on one side of the blank, and the gas cap key on the other side and then one key will fit both locks.
It just means that if you put the key in and it won't turn, just take it out and turn it over and it will work. Total cost? $1.00 to cut each key.
I now have 3 dual purpose keys for my bike... the ignition side even opens the helmet lock.I just had to pass this on to others who may have this problem.

-John