Changing altimeter

The process is the same for any aircraft with 2D gauges.

http://flyawaysimulation.com/forum/topic/27907/altimeter-setting-mooney-bravo-ifr-panel/#ixzz1dgzBEMuo

You have to go to [Settings-General, International] on the main menu and change the Unit of Measure. The setting scale will remain in US inches but the weather setting menu will show millimeters.