Sorry, I forgot to mention the part about bags... For both of these bus transfers, you'll have to pick up your bags before bus transfer and recheck them upon arrival after bus transfer:

KIX->ITM->NRT
- pickup bags at KIX
- recheck bags at ITM (but all the way to SFO)

KIX->HND->NRT
- I think you can check your bags all the way to HND from DPS; anyone out there know for sure?
- pickup bags at HND
- recheck bags at NRT