Best ratio for GSC 3 blade 582?

I soon need to order a new C box for my 582. I will be running the OEM GSC prop (came with a Kitfox III from Skystar) for the near term, then hope to head towards an IVO or similar down the road.

My engine was originally equipped with a 3.0 ratio. Is this the best ratio for a GSC, or would it make sense to move to a 2.62 ratio?

Anyone run a 3 blade GSC with a 2.62 ratio box on a 582?

3-1 ratio on C-box worked well for 66"&68" 3 blade GSC & 68"&72"IVO light props on my Mk 2.Static RPM of 6150-6200 was obtained with all props.,with cruse around 75mph @5200 RPM.GSC 66"& 68" also worked well with 3:47-1 ratio.
Regards
Fred