I mind that part is the most hard to do, I have knex almost 15 years, and I create a car with suspension and direction 4 years ago.
Here we go...
Step 1: McPherson
I start to build the McPherson supension in the front.
Step 2: The Center Part, This Conect the Supension With the Car
Step 3: Part 3
I will build a half of the car with colored pieces.