All the clusters on eBay that are marked as '04+ GT (If they really are) that I looked at all had the second connector. Maybe the US based GT's are different with the connectors than the base?
Also, did you reprogram the mileage yourself or through a dealer? Cost?
In that I have only actually had my grubby hands on the clusters from 03 and 04 base, I can't testify with absolute certainty, that the 04 GT clusters have one or two connectors, so I guess its possible.
I couldn't find any on ebay one way or the other. Either they don't show the connectors, or the cluster is marked as fits a GT, but has the base 6400 redline and 120 mph top speed , instead of the GTs 8000 rpm/140+ mph
I set the mileage myself, using info from viewtopic.php?f=28&t=26526
, and an old laptop that still had a parallel port. Was careful to set it to actual mileage to not be fradulent.
The only easily available wiring info is from a softcopy of the 03 Matrix manual that some folks have posted online, and that doesn't seem to have a consolidated cluster wiring diagram, the cluster is shown in various other circuits. Actual GM Vibe info seems to only be available from buying the expensive official GM service manuals from Helm. I bought a set for an 03 Vibe, and somehow lost volume 2, which contains most of the wiring info, but thats for an 03 and wouldn't help you if I still had it. (I'm still pissed at losing that book) There's an 04 set on ebay for $220, which is nuts. I don't know if anyone still active here has an 04 set, or an 05-08 set.