Right click then click save to file.
It'll save art of that part to file. It'll have size of this albedo.

Right click then click load from file.
It'll load an art to this part, exchanging old one to this one. Old mesh will be inherited.

Right click then click make emissive.
It'll create an emissive with same art as albedo.
You can check emissive working by enabling post processing.