Instruction on read and write an ECU BOSCH ME7.4.6

I must change my ECM Bosch ME7.4.6 (on Citroen C5 V6 210HP 3.0l petrol) and I try to retrieve the contents of the eeprom 25C16 (immobilizer) and eeprom AM29ff400 to rewrite on the new (used). The BSI is original.
I currently own the Citroen tools after sale (Diagbox-Lexia) that does not allow access to the contents of the eeprom 25C16.
I wish to prevent desoldering components.
I wonder if I can use a Galletto V2 with BDM probe (JTAG) and if so how in practice. I noticed that on the ME7.4.6 there was a series of copper pads probably destined for testing and programming module.
Then I got reply that reading: you cannot connect to ME7.4.6 with BDM…there is no pins on it.
You have to work in boot mode.

Full backup in boot mode can be done with KTAG – that’s the best choice, than you can make complete clone of the ECU.
But desoldering immo chip is very easy  2min job…

Flashing of eeprom can be done with galletto in boot mode or mpps v12 as well (generic mode). PS: a galletto 1260 is enough, with MPPS V12, the connections with the plug OBD are the same that with Galletto.