Carbonfiberboy gave good advice.
I thnk the course is fine. A few tips:
1) Don't start too fast - you should take about a minute to hit top speed/exertion.
2) Don't push the pace when the hill gets steeper. You won't have any extra to give, so you'll have to slow down on the hills.
3) Take 10 minutes to recover between the efforts.
If you wanted to, you could do the Carmichael version of the test which is only 3 miles long. That would let you start on the flat part just after a mile on the plot. It's a slightly shorter test, so the average heart rate will be a bit above the LT (say, 3-8 beats), but it's not enough to have much effect on HR ranges.
Either way, it's going to be very painful.
Finally, doing these tests is a learned skill, so don't expect to be able to do it perfectly the first time. I generally do better on my second effort rather than the first one.