Flat rate breakdown

[128degreestoday]

I am looking to see how others breakdown a flat rate item when you show the part being covered under parts warranty.
An example: condensing fan motor. Flat rate installed/replaced 450-650. 1-Show the part covered at higher cost (x2)and credit it onto the invoice and then the difference =labor/install? If not x2 then install / labor may appear too High . How do you invoice a covered part motor, board (parts other than compressors)