De Minimis Safe Harbor Election - How to expense the cost of Labor?

I am familiar with the process on how to use the De Minimis Safe Harbor Election for items. My question is how do I expense the cost of the labor?

 

Ex. I purchased a new water heater that cost $800 and I paid the plumber $200 to install it. I bought the water heater at the store and paid the worker when he was done with the installation. One receipt has the total purchase of the water heater and the 2nd receipt is from the plumber for $200 for the installation. I do understand I can expense the water heater using the De Minimis Safe Harbor but according to the TurboTax help section the De Minimis Safe Harbor election states the following: "This amount doesn't have to include costs like delivery or installation fees, unless these costs are already on the same receipt as the item."  Since I have 2 separate receipts how do I expense the cost of the $200 labor that I paid the plumber for the installation?  

 

Thank you,

David