A seed planting unit of an agricultural implement may include a wheel support arm having an upper portion and a lower portion, the upper portion defining a depth adjustment slot. A wheel may be rotatably supported by the lower portion of the wheel support arm, the wheel configured to contact the soil surface to define a penetration depth setting for the ground engaging tool relative to the soil surface. A depth adjustment lever is selectively movable relative to the wheel support arm to vary the penetration depth setting for the ground engaging tool. The lever may include a guide pin that is configured to be received within the depth adjustment slot, the guide pin configured to move within the depth adjustment slot as the depth adjustment lever is moved relative to the wheel support arm to adjust a vertical position of the wheel relative to the ground engaging tool.
