Translation rate change in 11i from historical to period

I have a handful of balance sheet accounts that I needed to adjust the translation on...  I am trying to MAKE the GL agree with our PUBLISHED financial statements.   I did this by entering in historical rates....

Now that the changes are made and everything is tied out..

I want to go back to letting the balance sheet accounts translate using the period rates (Month End)...  how can I do this?  Or do I need to continue to enter histocial rates for these accounts every month going forward.

The user guide says to delete all the historical rates for these accounts... when I do this...the translated amounts change with the next translation.