Has anyone been successful in performing a transplant - swapping SPFs from the monochrome machines that had this SPF (MX-M365N/M465N/M565N) to the color machines of this era (MX-4111N/4141N/5141N) that had the same SPF or vice versa? I tried putting a MX-365N SPF onto a MX-4141N and it feeds the document into the center of the feeder and registers a jam with the jam code of ICU_REQ. Will feed all day long in SPF aging mode via the Sim 2-1. The RADFs swap across product lines, and even across generations with no problem. Perplexing......