Don't use green-out. Draw a single line through the incorrect entry, with a note "corrected totals on <date>", then make a single line entry in your logbook (at the next open line), titled "corrections to flight time" or something like that, with the changes that you need to make in each column. You could also reference back to the incorrect dates in the remarks column to allow easy corroraboration in the future.
<That doesn't read very clearly, so I'll try again>
I did this on some entries that I decided were incorrect, something like four years after they were intially made. I certainly didn't want to change the totals on every single page for the whole four year period, so I made the correction to the totals on the last (most recent) page, with notes on where to find the original error. The page that has the original error has a line through the bad entry, with a note where to find the corrections to the totals.
Hopefully one of those descriptions will make sense. /ubbthreads/images/graemlins/confused.gif /ubbthreads/images/graemlins/smile.gif