2008 spa v Thai euro4

[AWO]

So I’ve got a spa d40 needs a new head.
A bloke I know has got a Thai d40 needs new injectors. I also looked a new engine for the spa from a wrecker, who tells me it’s Thai but will go in and work but I must put the span fuel pump and injectors on the new long engine. (From the Thai)
I asked why this was? Will the ecu not recognise the other pump and injectors? He said nothing to do with ecu, ‘they just different parts’ 
my question is are the pumps interchangeable? They seem to be. and will it run if I code in  the new parts? 
anyone ?