I hit this wall hard too when reordering ink! I could not find an old to new translation page on Epson's website, that would have been helpful. Also, B&H says the new cartridge codes are for the "7800 and 9880" and do not mention the 9800; but I have used some of the new inks in my 9800 without problems (I'm not talking about the new vivid color).
So, here are the old codes, before there were new codes, and also the new codes.
Light Magenta:
220ml: T603C00 (was T563600)
110ML: T602C00 (was T562600)
Magenta:
220ml:
? (was T563300)
110mL: T602B00 (was T562300)
Light Cyan:
220ml: T603500 (was T563500)
110ml: T602500 (was T562500)
Cyan:
220ml:
? (was
?)
110ml: T602200 (was T562200)
Yellow:
220ml:
? (was T563400)
110ml: T602400 (was T562400)
MK:
220ml:
? (was T567800)
110ml: T611800 (was
?)
Light Black
220ml: T603700 (was T563900)
110ml: T602700 (was T562700)
Light Light Black
220ml: T603900? (was T563900)
110ml: T602900 (was T562900)
PK:
Don't know, don't use it, perhaps someone could help here.
For anything with "?" I was not sure. I used the B&H website for the above, please post corrections if I am wrong.
Disclaimer: This post is for entertainment purposes and there are no guarantees that this information is fit for any purpose. Verify these codes before placing any orders.