Gst - billing to whom?

As per my opinion, Invoice should be raised on the person to whom service has been provided which is in your case is customer.

Insurance co. merely kind of reimbursing the part amount but the ultimate service recipient is Customer.

For Eg. If spare parts are fitted in customers vehicle then bill must be raised on customer only since he is the receiver of inputs i.e. spare Parts.  It will not be appropriate to raise invoice on Insurance co. because although it has provided part of the consideration, but it did'nt receive any inputs.

Other views are also welcomed.

I am also having same opinion but then why automobile companies are following the system of separate billing part bill to insurance company and part to customer of thier respective portion... in this all insurance company is only the party which reimbursing the customer loss.. but ultimate service is received by customer only..so i have to billed to customer only..it is not my lookout how customer will pay me.

More opinon required.. 

If separte billing to be done, please explain the same.. why so or where in GST Act it is mention that to do so.