This is for the budget conscious swapper who is preparing to swap the 2zz into his/her Toyota MR2 spyder but is working with a tight budget. This option requires you to sent us your OEM 1zz harness, we will make all the wiring modifications for you and ship it back to you. Once you receive it back it will nearly be plug'n'play with 2 simple modification to your body harness with clear instructions. This will eliminate the electrical confusion some have with this swap while saving you money.