i know this has been beat to death but is it possible to have both.
it seams that my 1999 has 1999.5 and E1999 stuff.
my suspension is 1999.5 as is most other items but i have alot of early 1999 barts also. i dont have the "wicked wheel", I dont have the late style intake heater. it (Had) the late style air box, it also has the early style powerstroke badge by the headlight. i dont know what month is was made due to the door stickers missing. im just woundering if it is possible to have been made right when the changes were being made so it got both parts?

 

Sounds to me like you have a late 99... I am betting money you are looking in the wrong location for the intake air heater.

The door badge could be someone changing it, or the truck being wrecked.

 

I have an early 99 as well and there is a provision for the intake heater but it's plugged. It's located right where the outlet from the intercooler drops into the intake, right on the spider.

 

Your truck reminds me of the Johnny Cash song "One Piece At A Time". I'd say E-99 that had issues and they took parts from 99.5+ trucks to fix it.