Few questions about fuel injector part numbers for 335i E92

[LaFuriaRoja]

2006 56 plate 335i E92 @ 70K miles. Replaced coils and sparks.

So I've got to replace injector #1. I can change just the 1 rather than the whole bank, as long as all the injectors along the bank of 3 are matching.

I've checked out the injector numbers I have, and they're all 1353 7537 317 - 08.

When I come to replace the bad injector, does it have to be exactly "1353 7537 317 - 08"?

Or is it that the first part (1353 7537 317) has to match and the index (08) can be different, as long as the index number is "10" or lower? Or that the first part can be different, and the index number has to be "08"?

Also, been talking to EuroCarParts, who linked me to

http://www.eurocarparts.com/search/431110560/p/hom...

for the fuel injector. However, there is no part numbers similar to "1353 7537 317 - 08" on the website. How am I supposed to get the exact part? Is the only way by telling them to check the product beforehand, because that would rule out online ordering.

And the last question. Doing a bit of online research, a few people seem to suggest that the injectors were updated twice after the originals. The numbers look something like this:

Latest: 1353 8616 079
Previous: 1353 7585 261
Original: 1353 7565 138

Aside from the first 4 digits, why do the rest of these part numbers look completely different to mine?

Any help much appreciated.