Alpha 2.0 is wider.
The Alpha 2.0 laser tilt mount has the calibration sensor near the middle of the back of the tilt rack. The Alpha 1.0 mount has the sensor near the bottom back of the frame, and is thinner. If you have an Alpha 1.0 mount, press 'Cancel' and select 'Laser Tilt Alpha 1.0' from the menu.
The laser tilt may have a guard above the E-chain. If it does, it is an Alpha 1.0 version. Not all Alpha 1.0's have the guard, so be careful.
Do not proceed if you are not sure.
Press 'Continue' to proceed.