Another Master cyl question

[halfcockedcustoms]

I am finally switchin to a dual pot master(also puttin disc brakes on the front)..I've read up on the threads many times,,but I have made myself confused a lil...I am stickin with manual brakes and got a master for a 72 manual disc truck..This is where I am confused,,Do I need to extend the pushrod for this master? The bore size in the stock single and the new dual pot are the same size/depth...Can somebody please unconfuse me..Thanks