Am I going to have to take the bumper completely off of my '06 to install HIDS in the headlights and foglights? Also am I going to need the relay or anything? I was reading on here something about the foglight issues...

 

You shouldn't have to remove the bumper, but the relay is something I think you need. That is why complete kits are the best. I am getting one for my Mustang asap!

 

^^^^^Like was said above get a complete kit like from Stangmod they have a lifetime warranty on there lights they might be a little $$ but its worth it to be able to get them replaced for free. You will not need to remove the bumper just the radiator cover and you can tuck the wires along the top side of the radiator, and they come with a relay, its pretty simple to install.
Javi.....

 

i found that DDMtuning has a lifetime warranty as well and they are half the price. i had a set of HIDS i payed $354 for when I was 17. Top quality McCulloch kit - and shortly after, i bought an ebay set for $40. there is absolutely no difference in the kits.