Will these work with an M Sport or Performance bumper?

No — these are designed for the OEM base bumper only. M / Sport Package bumpers have different reflector positions and housing depths, so fitment won't work.

Do these come with wiring harnesses or do I need to transfer mine?

Transfer your existing wiring harness from the old reflectors. The housings themselves are the swap — plug-and-play into your bumper cavity.

Can I install these without removing the full bumper?

Access from behind the bumper is tight but doable on some setups. Removal makes the job cleaner. Test your wheel well angle first — you may be able to reach the housing clips without full bumper drop.