A stump cutter comprising: a boom-mounted cutter wheel rotatable about a cutter wheel axis, wherein the cutter wheel is supported by a boom for sweep movements about a vertical cutter wheel sweep axis so that the cutter wheel sweeps along an arcuate path within a horizontal plane, and wherein the cutter wheel is supported by the boom for tilt movements about a horizontal cutter wheel tilt axis so that the cutter wheel tilts along an arcuate path within a vertical plane; a prime mover configured to drive the cutter wheel about the cutter wheel axis, wherein the prime mover is supported on a mainframe of the stump cutter and does not move with the boom; and a mechanical driveline configured to provide power transmission from the prime mover to the cutter wheel, the mechanical driveline including a final drive cutter wheel gearbox positioned along the cutter wheel axis, a swivel gearbox assembly including two right angle gearboxes (150, 152) joined with a swivel joint therebetween, wherein the swivel joint between the two right angle gearboxes (150, 152) forms a driveline swivel axis, and an input shaft of an upstream one of the two right angle gearboxes (150, 152), the input shaft defining an axis fixed with respect to the mainframe and the prime mover, wherein a downstream one of the two right angle gearboxes (150, 152) includes an output shaft connected to an input shaft of the final drive cutter wheel gearbox. a boom-mounted cutter wheel rotatable about a cutter wheel axis, wherein the cutter wheel is supported by a boom for sweep movements about a vertical cutter wheel sweep axis so that the cutter wheel sweeps along an arcuate path within a horizontal plane, and wherein the cutter wheel is supported by the boom for tilt movements about a horizontal cutter wheel tilt axis so that the cutter wheel tilts along an arcuate path within a vertical plane; a prime mover configured to drive the cutter wheel about the cutter wheel axis, wherein the prime mover is supported on a mainframe of the stump cutter and does not move with the boom; and a mechanical driveline configured to provide power transmission from the prime mover to the cutter wheel, the mechanical driveline including a final drive cutter wheel gearbox positioned along the cutter wheel axis, a swivel gearbox assembly including two right angle gearboxes (150, 152) joined with a swivel joint therebetween, wherein the swivel joint between the two right angle gearboxes (150, 152) forms a driveline swivel axis, and an input shaft of an upstream one of the two right angle gearboxes (150, 152), the input shaft defining an axis fixed with respect to the mainframe and the prime mover, wherein a downstream one of the two right angle gearboxes (150, 152) includes an output shaft connected to an input shaft of the final drive cutter wheel gearbox. a final drive cutter wheel gearbox positioned along the cutter wheel axis, a swivel gearbox assembly including two right angle gearboxes (150, 152) joined with a swivel joint therebetween, wherein the swivel joint between the two right angle gearboxes (150, 152) forms a driveline swivel axis, and an input shaft of an upstream one of the two right angle gearboxes (150, 152), the input shaft defining an axis fixed with respect to the mainframe and the prime mover, wherein a downstream one of the two right angle gearboxes (150, 152) includes an output shaft connected to an input shaft of the final drive cutter wheel gearbox.