Will this lens pop straight into my existing mirror housing?

Yes—it's designed to use your factory mounting points and housing without modification. The OE curve matches what you have, so alignment is straightforward.

Does this come with any adhesive or fasteners to secure the lens?

The lens itself ships without adhesive or hardware. Your existing mirror housing likely has its own mounting method—verify how your current lens is seated before removal, then use the same approach for installation.

What if the lens doesn't seat flush after I install it?

Test-fit first with the mirror housing loose. If there's a gap at the edge, check that the housing itself isn't warped and that you're seating the lens all the way in. Contact support if alignment stays off after a careful second attempt.