I went with @Blooie's suggestion of using an old towel and just tossing it when I took the MHP out,
but I had a P&S covered piece of thin plywood under the towel(good thing too).
Hi @aart I thought that @Blooie's suggestion was to cover the old towel with the P&S. Not really worried, since it has only been in the past 3 days that they have been hopping up there. They are growing out of the space, and it is time to move them out. Luckily, I sold 4 chicks over the weekend, so there are only 5 under the MHP.
I'd love to see a photo of your MHP set up.