Welcome to the journey! Glad you are having fun and success with your horse. Level 2 is so much fun, you and your horse will have a blast! Level 3 is even more fun, but way more challenging lol!
So, if you think about the ingrediants that make up the sideways game, Level 1 style, what are they? Friendly and Driving games. So, are those games broken? Is your driving game really good, especially with this front end? Can you play any of the games and go immediately to Friendly and have him be confident?
If those games are good then we can address you! Lol. Body positioning, energy, use of tools and Zones, etc. Stick close to the fence, outside hand held straight out in front of you, just like in the DVDs. You will need to find an energy that is appropriate for your horse. Too little and he won't move, too much and he will pull. So experiment.
One thing you need to make sure is in place is your half circles. Can you easily send your horse out and away from you while your back is to the fence? Send him back and forth until it becomes easy. Then, as he's going, when he passes you start walking down the rail, arm straight out, your other hand using your stick, and focusing down the rail and WALK. Don't stop, you keep your feet moving. If he starts slowing down, that's his problem. You keep walkin. If he gets fired up back your energy off and slow down some, but keep walking. Reward the slightest try.
Hope that helps some! Good luck and have fun!