One example provides a grinding positioning plate for a reel-type mower unit including a cutting reel having a rotational axis. The grinding positioning plate includes a main body including a pivot element having a pivot axis, and at least one pair of clamping assemblies, each clamping assembly to clamp to a corresponding mounting flange of the reel-type mower unit to mount the main body to reel-type mower unit such that the pivot axis is in parallel with the rotational axis and at a known horizontal distance from the rotational axis.
