MRP is generating messages for Co-Products not Process Item, any ideas why?

I am assuming there is an issue with our set up or processing options somewhere but I can't figure out what.  According to document 642021.1 MRP should be displaying messages for the process item but it is creating messages for the Co-Product Items instead.  I was not able to find much documentation on how things should be set up to get this to process correctly.  Any information you could provide would be greatly appreciated.

From Doc 642021.1

 

Planning may be done for the Process using either the R3482 or R3483, by adding forecast or demand on the Co-Product item.  The co-products are the actual products being sold.  Companies may also sell their by-products but these are never planned as suggested output by MRP and act more as scrap or shrink in a Process.