I have a 1997 2188 with AFS with the first yield monitor that came out. I noticed that there are a few complete units off 2388's available with the newer style monitor. Is it possible to retrofit a 2188 with the 2388 yield monitor system, or don't the sensors interchange? I know mine has the sensor at the top of the clean grain elevator, and the 2388 is at the bottom I think. The other option is to go with a complete Ag-Leader system for about $6000, but paying $2500.00-3000.00 is preferable for me if it can be done. What are your thoughts?