Do these mount at the factory cab light locations?

Yes. These are designed for factory cab light mounting points on your Ram — no drilling or relocation needed. Your existing electrical connectors will plug directly in.

Can I swap just the bulbs if one LED burns out?

Bulbs are integrated into the housing assembly. If an LED fails, you'll need to replace the entire light unit rather than swap a single bulb.

Will the smoke housing dim the light output noticeably?

The smoke lens darkens the appearance of the light, but LED output is bright enough for functional cab illumination. You get style without sacrificing usability.