Gotta say that when I transitioned from the "Classic" to the "400" that I found it was (in the end) easier to maintain a more accurate altitude.
These days of course, the only places you can normally hand fly at 37,000 ft are in Afghanistan and Antarctica (on our company's routes).
The technique I tended to use (which is what you are searching for) was to keep the VSI pointer pointing at the Altimeter number you wanted.
hth.
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