Launch control / anti lag switch wiring location

[Brad98e36]

Hey new to this form been completing my 1998 m3 project. Link g4x ecu all installed and wired up. At the finish stage I picked up a motion raceworks dual button for steering wheel , 2 buttons 2 wires each + and -. Now where should I pin these on the ecu location one being launch control and other being anti lag. Should I run just the red wire to ecu and ground the other on the chassis? Or is a ground in the ecu preferred?  
Any help would be greatly appreciated. I know I have to setup on pc link side once installed. Just confused on location for the 2 wires on each momentary buttons . I have included photos of the buttons and information on them 

[Adamw]

Ground one side of the switch, chassis ground is fine, connect the other wire to a digital input.  Assuming the switches are normally open type, the DI settings will be pull-up on, active state low.