A co-worker of mine has an 04-08 (cant remember exactly), supercrew 4x4. its an xlt or lariat. We were talking about how easy it is to add cruise to my truck when he asked me about door buttons

Would it be as easy as buying an outside, driver's door handle with buttons and putting it in? are the wires already inside the door? I would check with my truck, but I figure an all-manual XL probably doesn't have any wires in the door besides speaker wire.

my biggest question would be the code. is there a "brain" somewhere that controls this?

 

yes there is a security module.there is a key pad that ford has that is wireless but you need factory remotes.

 

"factory remotes" as in keyless entry? I should have clarified, he does currently have the keyless entry keyfobs. I'll do some searching for the wireless keypad, thank you

 

yes if it has factory keyless you can add a ford wireless keypad..
it programs the same as the remote.. turn key off and on 7 times, push in the code hit lock on both the factory remote or they will be erased then stick it to the door