Brand new brake master cylinder failed, help!

[Isaiah92260]

I bought a round top Brake Master Cylinder. Assuming that was the right part I needed, my fault for going to AutoZone I guess. The only had the round top single master cylinder and a dual master cylinder. I have the 1 1/8th single master cylinder with the square top originally.... After doing research and a lot of brake bleeding, the new round top would not work! Also found out that the round top is 1 inch bite and the original square top Style is 1 1/8th bore.... Pedal down to the floor, I adjusted the push rod all the way and I had 2 inches of play before it started engaging..... Where are can I find the square style master cylinder? Or do the still make them? Or are there any more alternatives I can try before I attempt to return the brake master cylinder to autozone? Are longer brake push rods?