The original SpartaDOS X cartridge from ICD contains 64kB of EPROM and is filled up to 99% with software. To add new functions one would have to remove "unnecessary" programs from the CAR: device, which is obviously not a very acceptable solution. That is why the new SpartaDOS X needs a cartridge with at least 128kB.
MEtalGuy66 adapted the instructions for the intSDX 128kB to the original SDX cartridge. This way, the modified cartridge can host the new SpartaDOS X.
The solution is described at AtariAge Atari 8-bit forum:
How to upgrade an original ICD SpartaDOS X cartridge to the new SDX.
MEtalGuy66 - hardware, DLT - software
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