Hey SML,
This is entirely up to you Bud, but, I've seen many DP units sitting on those yellow plastic blocks "under the tires". I've seen them stair step them to a height 5 or 6 and, they appeared to be handling the weight just fine each time I saw them in that situation. I have various thickness wooden blocks for my application but, I also carry about 10 of those too.
Leveling is always a debate here and on other forums. How people go about it, the procedures, limits to which they'll let their vehicles "hang" and more are always argued, one way or another. Now you, knowing that your new rig is "potentially" limited in leveling capabilities, might think about keeping maybe at least half of them around. Again, it's entirely up to you for a decision like this. I don't even know what kind of limit those are suppose to have. I just know I've seen them under some mighty heavy rigs. Your choice pal.
Scott