There should have been an instructions sheet in the box.......the one listed below was for the 7.3.....quite a while back.
Item#: BK 6053137
Price: $40.29
tax and shipping not included
Disclaimer: The stated price may vary from the in store price and may change at anytime.
Attributes:
Additional Contents:Engine Heater, Cordset,
Plug Protector & Installation Instructions
Cord Length:60"
Freeze Plug Size:1.5"
Manufacturer:Pyroil
Recommended Application:Varies
Recommended Element Position:Varies By Application
Recommended Location:Varies By Application
Replaceable Power Cord:Yes
Voltage:120 V
Wattage:1000 W
The orientation of th BH element is to the 11:00 position so as to clear any obstructions in the block. Just double check your truck requirements on the NAPA webpage. Do not overtighten......
NAPA web page