If you have second hand DSM with 3m25j and no special equipment, that i do today.
1. Read 3m25j EEPROM and save.
2. Fill all with FF and Write.
3. Install on car and adapted at end end of this stage you must have start authorization active.

4. Read again 3m25j copy all values fron adress 001EC to the end from original read to new read.
5. Write this file... install on car and that's all.