99gt to 04 cobra wiring question

ok novis question
i have a 99 gt and here is what i want to do i have some of the parts not sure what all im going to need
what i have
supercharged cobra motor with a cracked block
97 cobra block
i have what im told is all the heat exchanger stuff
the gas tank but not sure if its what its suspost to be i didnt pull the pumps and look
what wiring do i need do i need the gage cluster and ecu or can i use what i have and get a tweecer