I'm booked on a multiple leg trip from SFO to Europe on a combination of DL/KL/AF/AZ metal flights, with a mix of DL and KL marketed flight numbers.

I'd like to maximize miles into AS a much as possible (AS-eligible DL flight #s, KL flight #s), and dump the rest into Skymiles (DL codeshare flight #s).

From what I've read, DL is only able to place a single FF# on a PNR - has anyone had success with anything different, or not having a FF# on the PNR and doing a retroactive request after the trip?