Kyle Busch truck team going to Chevy  

I know that the major teams in all 3 Nascar levels get technical help from their respective manufacturers.  What I don't understand is whats the big deal of switching from Toyota to Chevy for Busch's truck team.  Correct me if I'm wrong but the only Busch would have to change would be the nose of the truck since, to my knowledge, all trucks run the Ilmorr engine.  I guess waht it comes down to is the amount of $$$$ is offered by Chevy.  I'd appreciate some imput on this from 3Wide nation, especially a certain Stewie supporter.  Scott Ely