Kops is mostly irrelevant. There are a lot of other factors that go into a proper fit and if you get everything dialed in, your knees will probably be about over the spindle anyway, on a traditional frame. But there's no need to adjust for that specifically. Saddle fore-aft will affect your reach and therefore your body angle, but then you've got frame size and handlebar height to account for also.

The Myth of KOPS