What I do on my 4550 is to use a low contrast (grade one) setting to do a test strip to determine the highlight tonality. Then I do a second test strip by exposing a second sheet of paper with the high value (low contrast) time followed by a second test strip on that same piece of paper at a grade five setting to determine low value times.

The actual printing then becomes X seconds at grade one followed by X seconds at grade five.

The burning and dodging will then be determined by the tonal range and the contrast grade at which it was printed.