Most older AT mbs require a 'kit' to complete the installation. I still am using a couple myself. The last time I needed the 'kit,' It was purchased on E*bay for about $15 bucks with shipping. Came with IDE/Floppy cables, a universal USB connector, a universal PS2 connector, mb screws, serial and Lpt extensions. I'm not sure about the IR module.
You need the pinouts to set up the 'universal' connectors.