D12D EGR disabling by new ECM. new engine harness and reprogramming VCU ??????

I have 2006 Volvo 630 with D12D 465HP engine.. recently started getting fuel injector electrical fault codes..
read somewhere that it might be some regulator or converter on ECM.. new ECM might be needed so thought
can I replace it with engine computer from pre-EGR engine.. will have to change engine harness,
since the plugs are located on different side of ECU along with different wiring as well , and program VCU with vin of the pre-EGR truck??

I have a dealer guy who would do all the necessary programming..

the only concern is if the Engine harness CONNECTION with other harnesses on the truck is still the same like on PRE-EGR trucks ??????