What is going to happen when I remove the master cylinder?

In my 66 dart, original drum brakes, single cup MC. Getting ready to swap it all over to disc so i bought a new MC with the dual cup, small bore, manual. It is my understanding this new MC is bolt on, and reuses the brake push rod. So is it really, jst remove the old MC, and then bolt up the new MC and it will connect to the old Push rod?? Or am I also removing the push rod??
thanks for any help.
and yes I am running new brake lines .