Do these bolt straight to the factory mounting points?

Yes—these mount at the factory locations with no drilling or modification needed. You're pulling off the old unit and bolting the new one in the same spot.

Are the H13 bulbs any good or should I replace them right away?

The included bulbs are functional and come with the assembly. If you want different brightness or color temp down the road, H13 replacements are cheap and widely available everywhere.

Will I need to adjust the beam angle after installation?

Most installs work plug-and-play, but always do a quick parking lot aim-check after you're done—point them at a wall 25 feet out and make sure the beam is even and not too high or low. Small Phillips adjustment screws on the back of each unit handle it if needed.