Hi ely,
I've owned and played on quite a few GCs over the years.
IMHO - it is almost certainly not a GC3.
Most likely choices:
1. A "late" GC2 - they made some with the 'factory' brown stain but the
silver feet and castings.
2. A "stained" pre-3. In the 80s there were lots of GC1s & GC2s that
got re-worked and stained to look like a GC3.
In your pic, to me, the aprons look much darker than the legs(pedestals).
That would argue for a re-worked version.
FWIW - I prefer the GC2 - there were issues with the glue Bruns used
for the cushions on GC1s, I never saw one that didn't have dead spots
where the gluebond had failed.
As for the GC3, well...
Dale