EFI differences on the Magnum???

Is there any difference between the EFI on a 5.9 91-95 vs. the EFI on a 5.9 1999?

All i can this is that after 96 the ecu controlled the auto trans.
TPS, Dissy, Crank Trigger, injectors, alt, and oil pressure sensor. should all be the same? Right??

Just looking for some clarity on this.

I have a 99 5.9 with all the accessories except the harness and ecu
I want to run the efi and use 393foureyedfox's harness but he says it only works with the
91-95 setups.
I have looked and can't find any differences other that the trans control change.

So the next big question is can I use his harness and a 91-95 ecu with my 99 parts?
any and all input it is welcome....
Thanks.