VTech Toot-Toot Drivers 4-in-1 Raceway. Instruction Manual page 14

Once you've completed the above steps, the 2-car raceway is ready
to play.
Duel Raceway
1. Disassemble J, K, G, H and I. Slide down G to the second floor,
2. Insert I into J, then slide down J to the first floor as shown below.
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