[cypher]

It is a good idea, he'll be much safer & more comfortable in a cage with one level & it will be easier for him to get to food & water without struggling or risking falls.
As CB if you use the substrate from the current cage he should settle fairly quickly, don't do any cage cleaning other than spot cleaning for a few weeks before or after so everything keeps his scent, try to move his nest material over too & keep the house he's used to sleeping in.