1500 quad cab hemi long bed with 20" wheels?

From : chris

Q: i have had dealers tell me that the 20tires/wheels can be ordered for a long bed quad cab. and others have said it will void the warranty so they cant order it this way. i liked the ride of the 20 wheels on the short bed. but i would also like a long bed. is this possible one dealer even told me you can put them on after you buy the truck and if it ever needs warranty work just swap the wheels till it is done.i think it is a safety issue. .