alright fellas, the ? is i believe the original harness in my civic right now will fit on to the b18 with little to no mods is that correct and my civ is multi- point already so dont have to worry about that....

 

B18 what? B18 OBDwhat?
What year Civic coupe?

You will use the stock harness. Depending on the year of the motor you are putting in and the year of your car which you haven't provided, will depend on what work will need to be done to adapt, or which harness adapters will be needed -if any at all.

More information is needed, please provide so people can help.

 

its already a MPFI and its a 94 civic OBD1 i believe... B18c1 is what i wanna put in there a GSR Motor

 

Yes use your stock harness you will have to extend the o2 sensor wires because its in the cat on a gsr. Wire in vtec depending on the model of your car, and wire iab and knock sensor. You also have the option of using a US gsr harness and running iab, knock, and vtec from the strut tower plugs to your ecu.