Cessna 172F Heated Pitot Tube Help Needed

I'm doing a first time (for me) Annual Inspection on a Cessna 172F, S/N 
172526XX. Quite awhile back, both wings were replaced. It now has a heated pitot tube installed, but I suspect it may have come from the factory with a non-heated unit, as there is no pitot heat switch nor provision for same on the panel. What are the legalities on this? Placard it?
Install wires, breaker, and switch to make it functional for heat?   Thanks,  
Pridham