A/M ECU means aftermarket which is expensive if you just need boost cut removed.
Go for a small stand alone unit with the sole purpose of removing the cut. Have a search on the HKS and Greddy etc websites it should be listed there with full details on how they work.
removing the boost cut with a Fuel cut defender will make it run lean past 12psi.. not a good idea.. there are other ways around fueling above 12psi without a standalone ecu tho.