Hi there, In my theatre, we own several hundred ETC Source 4's. Over the past few years, several caps have died and need the porcelains to be replaced. When we ordered new porcelains, they sent us new and improved ones that do not fit into the older slots. We've tried grinding the porcelains down, cutting them to fit, aiming shrink ray guns at them...etc. Does anyone know how to address this issue or where to purchase the older porcelains. Anything besides having to purchase the entire cap.