Best way to make wheels freely turn / swivel? (Like a shopping cart)

I’m trying to make a trolley-like object where the front two wheels freely spin and turn and the back two wheels only free spin. So far I have all four wheels freely spinning with Wheel Colliders, but I’m having trouble configuring the front two wheels to freely turn as well. When the object is placed on a slanted incline, the front wheels should begin to point downhill and then straighten out (just like a shopping cart). Currently, the hierarchy for this thing is

->Gameobject with Rigidbody

—>Cube body with Box Collider

—>Wheel FL with Wheel Collider

—>Wheel FR with Wheel Collider

—>Wheel BL with Wheel Collider

—>Wheel BR with Wheel Collider

Not really sure the best way to go about this, so any help is appreciated!

woud you mind showing the code? This might help.

Not exactly what you asked for but I solved a simular problem with replacing the front wheel with a physics material with no friction on it applied to a sphere.