As above, two thick hard foam cushions, one under and one behind. In my experience you can get the leg position OK on the clutch for a 5' 2" driver with the seat right forward, the pedals in the closest position and a 50mm cushion.
The driving position in the 7 is so different that it's hard for new drivers to get it right. It's not uncommon for them to be happier in a longer position after a few miles. Any chance of practicing somewhere private to make it easier to get started?
Jonathan