I'm Pretty sure my Bearded dragon is a Lawsons

[CooperDragon]

You could set it up either way that's more of a preference thing. I use two 18x18'' tiles in my 36x18x18'' enclosure. A 40g breeder has the same footprint so the same sized tiles should work. I bought a 6 pack for about $10 at Lowe's and they cut them down to 18x18'' for me at the store for free. I just use two at a time and swap them out when they get dirty. I have found that the constant hard surface can cause some irritation on their palms after a while so keep an eye out for that. I wound up putting small fleece blankets on half of the tile to provide a softer surface. That experience may vary though and my dragon's nails don't grow at all for some reason so the nail trimming is a non factor. I just find tile easy to clean and sanitize.

 

[Shidohari]

given that what I may do is have them cut it down to 18x18 as you suggested and only put it on the half that holds the food and water to lessen that as I my base substrate I use is repticarpet. that way it's not always on that rough surface.

I'll give that a try.