Development Blog, Grand Prix 1973 Grand Prix BT42 Development: Day 2 Posted on March 14, 2021April 14, 2021 by admin 14 Mar Day 2: Front suspension, mirrors, engine cover, rollcage, headrest, windshield + minor details. BT42 is gaining shape nicely. More development updates will be available soon. Grand Prix BT42 Development: Day 1 Grand Prix BT42 Development: Day 3: The Engine