[Mikes 300C H.E]

ok i got a quick question,

i leased my car for 3 years and 36K miles but ive already added some mods such as: K&N aircharger JBA EXHAUST JBA HIGHFLOW CATS airrad throttle body spacer and on order is diablo tuner and jba headers, but im plannin on returning it all back to stock before i turn it in, DOES ANYONE THINK ILL HAVE A PROBLEM???? Please let me know cause i didnt think it would be a problem but after reading this thread....