Originally Posted by Gkap
you can modify the car as much as you want just keep all of your
stock parts and put them back on before you return the car.
^^^^^^^ This .... only why would you spend all that cash? why not use the money for gas and enjoy driving the car ... think about it.
In any case ask the dealership they will tell you clearly and to the point what you can do and what not. Whatever they tell you make sure you make it part of the contract a lot can happen to the dealership during your lease turn. People will change jobs, leave ... dealership can be sold etc.