I had to try this one twice myself. The problem the first time around was that I did not really read the scenario briefing.
As soon as you take the target city, alot of French troops will spawn. So I took another look at it, and realized a few things.
1. Cities mean nothing in this game
2. The French will spawn within your lines
3. They attack in force.
So, I decided to empty the city with the general in it, but not capture it, just leave a tank units next to it. Then I started to make a defensive position east of the city. Next turn my tank took the city, and all other units were out of their trucks and ready to defend themselves.
After that, it was only a matter of getting the general to the extraction points, and try to rotate my units, so that if one of them had taken a beating, it would be pulled back and reinforced while the others defended.
"Hun skal torpederes!" - Birger Eriksen
("She is to be torpedoed!")