Helix, the correction of atomic dates to calendar dates can be done via the redshift curve, which is exactly the same as the light speed curve. We have it up on our website here:
http://www.setterfield.org/timeline.htm
The correction curve is posted here:
http://www.setterfield.org/cdkcurve.html
By the way, the earth is closer to 8000 years old than six. The reason for the 6000 year idea comes from the Masoretic text which is the one used for the common translations of the Old Testament from the King James on. The translators producing the Masoretic dropped, for reasons of their own, I guess, a number of the "100" ciphers from the text when dealing with Genesis 5 and 11 and the ages of the ancients.
The more ancient Alexandrian LXX (Septuagint) has the original numbers, and it is this we really ought to look to if we want the age of the earth as defined by the Bible.
I know the difference between 6000 and 8000 means nothing in terms of comparison with the old age ideas of billions of years, but you'd be surprised (or maybe not) at the furor it causes among creationists!
At any rate, as far as the timing I am referring to, I hope the above links help. It might be noteworthy to point out here that van Flandern at the U.S Naval Observatory in Washington documented the fact that atomic and orbital times run at different rates in his paper published in the U.S. National Bureau of Standards, special paper 617, in 1984.