Removing heater system, have questions...

Hello! I am swapping all of the parts of my GS-R into a completely bare shell and I have some quick questions about the heater. Ok so I am totally removing my heater and all controls, do I need to have a heater core still? I think I will have to keep the heater core in there for the coolant to flow through but I am unsure and would appreciate any help anyone could give me with this.

If you want to lighten the car more I would think that you could remove the heater core and just buy some fittings from a hardware store that fit the tubing, and just make a loop in place of the heater core. This shouldn’t interrupt coolant flow, but will allow removal of the heater core.

Yeah I was also thinking of that, but I am not sure if I do that and have no heater core if the engine will run hotter.