yes you can switch. he makes tunes for all 3, then you load them to the tuner.

 

Got ya ill have to check it out later when i get to my computer

 

Haha had a 85 power ram w150 318 auto that thing was a DOG! Load of fire wood in the bed and if you stopped on a big hill might as well throw it in 4 lo cause it would almost stall out. Pretty awesome tho made out of all steel(no cheap plastic on them) had 2k lb on my dakota and still got the same mpg lol