There's a MACK LR Truck Wiring Manual PDF above the page.
The Mack LR is a specialized cargo chassis designed primarily for garbage trucks.
The truck has a low, forward-shifted cab, in which there are two steering wheels - left and right, and the driver can both sit and drive while standing.
The model is powered by a Mack MP7 natural gas engine (300-325 hp), combined with an automatic transmission.