ok i need some one to set me some facts i wwas wondering lets say i wanted to swap a 97itr swap usmd into a 94 civic coupe ex how would i pass emission whats the rules of me needing to get it pass or i need to swap my sohc d16z6 back but its a hassle to do that i want to do everything legit i just need some real facts on this everywhere i look says you need paper work on were it came from or some sort of paper work that its legit is that true please i need somehelp i am confuse and thinking on doing this if its not a pain in the ass