@james @chrissie_c Yep, upon a closer look, the cable out looks like 13-pin - so a GK3.
I haven't yet cut over to Serial GK (GK5+) either. Soon though. There are some modelers coming using serial GK, I think due out in February 2025.
I hope you don't mind but I shared this pic over on vguitarforums.com!