the manual suggests the dealer do this, why?

I assume I will have to remove the bottom air dam from the backside of bumper to get to them, is that all?

 

Dealers need revenue, that's why!
To change bulb:
Remove undertray
Disconnect bulb multiplug from the bulb
Rotate bulb, remove, replace (don't touch glass part of bulb with fingers - if you do, clean it with denatured alcohol to prevent hot spots and premature bulb failure).
If you need to replace the entire light, just 3 screws to remove.
Cheers!

________

1999 XJR

 

thanks, did not look that difficult, but wondered if there was a special tool involved for some part of removal. Had that on another car, special tool turned out to be a torx head driver.