Hello me and my brother are arguing just how to make race bumpers! 1. Are they made with injection molding,(GFK is made liquid and injected into the negative shape) 2. Are they built with PvC, Gfk, Cfk etc. in the negative shape with plates (plates and harder) or are we both wrong??? Tuners like : EREBUNI, Onderground-design, Wings-West etc…. how are they manufactured there??? Injection molding/press or with Gfk … Plates??? So please answer quickly!!! thx!