A toner cartridge for use in an electrophotographic image forming device, comprising: a housing having a top, a bottom, a front and a rear positioned between a first side and a second side of the housing, the housing has a reservoir for holding toner; an outlet port in fluid communication with the reservoir and facing downward on the front of the housing for exiting toner from the toner cartridge; a toner delivery system for transferring toner from the reservoir out of the outlet port that includes a main input gear for providing rotational power to the toner delivery system, a top portion of the main input gear is exposed at the first side of the housing for mating with a corresponding drive gear in the image forming device when the toner cartridge is installed in the image forming device, the main input gear includes a rotational axis; a first alignment guide that extends outward from the first side of the housing and runs along a front-to-rear dimension of the housing; a second alignment guide that extends outward from the second side of the housing and runs along the front-to-rear dimension of the housing, the second alignment guide is parallel to and aligned in a vertical dimension of the housing with the first alignment guide; and a third alignment guide and a fourth alignment guide that extend outward from the first side of the housing, the third alignment guide is spaced toward the front of the housing from the fourth alignment guide, each of the third alignment guide and the fourth alignment guide includes a respective bottom surface (184, 186) that is unobstructed to permit the respective bottom surface (184, 186) to sit on top of a corresponding guide surface in the image forming device to control a vertical position of the toner cartridge when the toner cartridge is installed in the image forming device, the bottom surface of the third alignment guide is aligned with the bottom surface of the fourth alignment guide in the vertical dimension of the housing, the bottom surfaces (184, 186) of the third and fourth alignment guides (180, 182) are positioned higher than the first and second alignment guides (150, 170), the bottom surfaces (184, 186) of the third and fourth alignment guides (180, 182) are positioned higher than the rotational axis of the main input gear and are positioned closer to the rear of the housing than the rotational axis of the main input gear is to the rear of the housing. a housing having a top, a bottom, a front and a rear positioned between a first side and a second side of the housing, the housing has a reservoir for holding toner; an outlet port in fluid communication with the reservoir and facing downward on the front of the housing for exiting toner from the toner cartridge; a toner delivery system for transferring toner from the reservoir out of the outlet port that includes a main input gear for providing rotational power to the toner delivery system, a top portion of the main input gear is exposed at the first side of the housing for mating with a corresponding drive gear in the image forming device when the toner cartridge is installed in the image forming device, the main input gear includes a rotational axis; a first alignment guide that extends outward from the first side of the housing and runs along a front-to-rear dimension of the housing; a second alignment guide that extends outward from the second side of the housing and runs along the front-to-rear dimension of the housing, the second alignment guide is parallel to and aligned in a vertical dimension of the housing with the first alignment guide; and a third alignment guide and a fourth alignment guide that extend outward from the first side of the housing, the third alignment guide is spaced toward the front of the housing from the fourth alignment guide, each of the third alignment guide and the fourth alignment guide includes a respective bottom surface (184, 186) that is unobstructed to permit the respective bottom surface (184, 186) to sit on top of a corresponding guide surface in the image forming device to control a vertical position of the toner cartridge when the toner cartridge is installed in the image forming device, the bottom surface of the third alignment guide is aligned with the bottom surface of the fourth alignment guide in the vertical dimension of the housing, the bottom surfaces (184, 186) of the third and fourth alignment guides (180, 182) are positioned higher than the first and second alignment guides (150, 170), the bottom surfaces (184, 186) of the third and fourth alignment guides (180, 182) are positioned higher than the rotational axis of the main input gear and are positioned closer to the rear of the housing than the rotational axis of the main input gear is to the rear of the housing.