let me ask you this, why is there 2 different files of the same tunes on Smarty website? looks like one support 03 and not 07, but both support 06. should i use the one that supports 06 and 07?

 

Either will work for an 06.....the file is too large to fit into smarty and work from 03-07, so they split it up (03-06) and (04-07)....unless you know someone with an 03 or an 07 and you want to let them try it.....either will work for your truck....