Will the clear acrylic shields yellow or cloud over time?

Acrylic can yellow without UV protection, especially under constant sun exposure. Sealing the edges with clear silicone and keeping the shields clean will help slow that. If cloudiness happens, the shields can be polished or replaced down the road.

Do these mount using the factory window trim, or do I need to drill holes?

The visors are designed to work with the existing window channel and trim structure — no drilling required. Test-fit before finalizing installation to confirm your G6's trim matches the design.

Is the carbon fiber finish a wrap or paint, and will it need a clear coat?

The finish is molded weave-textured hard panel — not a paint layer. It does not require additional clear coat. The surface is sealed as-is, though you can protect seams and edges with clear silicone to prevent water infiltration.