The number of chains won't matter, but the '03 - '04 engines run on DME 7.8 and the '02 runs on DME 7.2. They have different variocam versions and the wiring is a little different. It will not be a direct replacement, but people have done it.
Here's a link to a comparison of the DME pin-outs:
https://www.renntech.org/forums/applications/core/interface/file/attachment.php?id=37889
You may need to be a member of Renntech to open that, not sure.
I'm picking up a neglected '04 tomorrow and
may play with running it on a DME 7.2, but don't think it will be simple or a good idea.