@gjacobse
OK, I checked now and the GX420T and GX430T is the same printer but with different dpi print heads.
If you can tell the application that prints to print differently depending on which printer you are printing to, everything will be fine.
If you can't, you have to replace those two GX430T printers with GX420T models.
Or put another way - if you want to have printers that are drop-in replacements for each other, you need to buy just GX420T printers (or other 203 dpi models).
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