Tandem T6 controls

The car drives with the game's normal controls. These are the extras. A short hint shows them each time you get in.

Action	Keyboard	Controller (Xbox layout)
Stats: card, live stats, off (cycles)	Tap K	Hold LB, click R3
Reset the timers and the top speed	Hold K (0.6 s)	Hold LB + R3 (0.6 s)
Get in as the driver	The game's Enter vehicle key (F by default)	Y
Ride in the back of a Tandem T6 driven by a friend or a companion	Hold Enter vehicle (F) next to it	Hold Y next to it
Get out (either seat)	The game's exit key (F by default)	Y

How the seats work

The driver sits in front and the passenger sits directly behind. Both get in through the front doors.
The rear passenger opens a front door and climbs through to the back, even when the driver is already in. They get out the same way.
Companions (bodyguards, friends) use the rear seat. They walk to a front door by themselves.

Card (shown for a few seconds when you get in): your best 0-60 mph, 0-100 km/h and quarter-mile times this session, the quarter-mile trap speed and your top speed, all measured in game.
Live stats: power in kW (and amps), speed in mph and km/h, motor rpm, then the timers, then body roll, cornering g and what the stabiliser is doing.
Timers start by themselves: come to a full stop, wait a moment, then accelerate. Hold K (or LB + R3) to clear them.

The keys only work while the game window has focus, and they are ignored while a trainer menu (such as Liberty's Legacy) is open, so menu buttons don't reach the car.
L3 stays the game's horn: the car never reads it.

Open plugins\TandemT6.ini in a text editor:

[Keys] Hud=0x4B is the keyboard key as a Windows virtual-key code: 0x4B is K. For example, 0x4C is L and 0x4A is J.
[Pad] ChordA=0x0100 and ChordB=0x0080 are the controller buttons as XInput values: 0x0100 is LB and 0x0080 is R3. Others: 0x0200 RB, 0x0040 L3, 0x1000 A, 0x2000 B.
[Pad] HoldMs=600 is how long a press counts as a hold, in milliseconds.

To apply a change while the game runs, change [Live] Serial (for example from 0 to 1) and save. The car reloads its settings within a second.