Here is a link to full schematics. Thanks to whoever made this. I just found a few issues with it. The CLK input to the 7474 on page 2 should be HRESET, not CLK. Also some of the nodes are inconsistently labeled.
Also see Reconstructing Pong on an FPGA by Stephen A. Edwards, which describes everything about the Pong circuit in excruciating detail. This was an enormous help to me in understanding the schematic; huge thanks to him.