Old post and the OP probably has is answer. But we just took delivery of our 2021 Reflection 315rlts, we installed the Lippert solid steps and used the four step model.Just bought a GD Reflection 315RLTS. I want to replace the OEM steps with the Solid Step. Has anyone done this and what was the part number? I think I need 4 step model, but OEM is 3 step.