RE: Calorie Surplus vs. Protein Rich
Muscle is made up of amino acids which are provided by the protein you eat. Your body has the ability to make the "non-essential" amino acids, but the essential ones must be supplied in the diet.
You need enough non-protein calories to perform the work your muscles are doing. Protein is used for energy reluctantly by the body by changing it into glucose.
So, muscle is built from protein, however, the energy to make muscles work are calories from glucose, fat and protein.