may be the way the bike set up as iv been running on the edge of the 60 and no were near the edge on the back so this is why im going to the 70

Just fit the bloody tyre and ride it ;)

3 laps at CC will be enough, just go steady loading the front and be smooth, and build your speed progressively. You can still go at tyre scrubbing speed and be only a second or two off a fast pace. It's only qualifying, not the race, so don't panic too much.

Then in the race, you can go like hell from the off.

Don't worry about it though, you'll do your head in.