I think most of the prototypes from the mid 70's followed the same design, gone were the curves of the late 60's and very early 70's that spawned the 917. 512 and Matras and early 33T's.
The later 33T, Mirage GR7, Lola 380 and the 2 litre cars of the era all shared the flat slab like sides.
It was not until the late 70s when the 936, and Renault Alpines arrived that curves were back in fashion.