I use the rear blade on my tractor to plow an ashphalt driveway with no damage to the pavement. Remember, road crews do this all the time using both front plows and grader blades below the truck. What road crews usually do with the blade under the truck in tilt the top of the blade really far forward so that it acts like a scoop instead of a blade.
Unfortunately, you can't tilt the blade as far forward as you can on a truck blade. Secondly, the rear blade on a tractor floats downward by itself unless you set the hitch lever control stop up far enough so that the blade is barely touching the pavement.
But you can do several other things. One is to adjust the top link to tilt the top of the blade back (brings the bottom edge forward & "up" slightly), so that it does not dig in. You're resting the blade on the back edge of the blade instead of the front.
The second thing you can do is turn the blade around 180 degrees so that the curved side is forward. Turning the blade "backwards" works just fine for 1-6" of snow. Using it backwards, you would want the top link adjusted so the implement is level.