stop coolant gooing to the heater core

Now that it is getting very warm out,when cruising even with the heater controls off there is still a lot of heat coming from the heater core in side the car ya too hot for me.In the past I have removed the heater hose's for the core and joined them so no flow to the car hence cooler cabin.I would like to keep things looking correct,so my Q is is there a mod we could do to stop flow to the core with out joining the 2 hoses together.