I level mine at an 8.5 degree incline. I just got off the phone with the technical personnel at Spot Hogg, and they said that's what everybody should do. It optimizes both the first and second axes, while allowing maximum margin-for-error in the third axis. Two standard deviations from the mean, that is.

If I were in your boat, I'd set it to level, then go up 8.5 degrees, and start tuning from there. I'd try that first with an offset left helical, and a straight cock vane. No matter what happens, keep checking your bubble. It can be really time consuming, but eventually, you'll get it - and you'll be glad you did!

Just remember, if it starts out nock-high, you went too far. Back it out and start over.