Yeah, you can edit the PCI ROM header of the ROM image to match the values of the Adaptec card. Just requires a bit of hex editing, no checksums need to be updated after modifying that header. The strings in the actual FCode portion of the ROM cannot be modified without other work, though. You will need to update a checksum after doing so, but you also have to ensure the FCode image length and block allocation is updated appropriately in the PCI ROM header (if your string changes cause the size of the file to change).