Help with mirror up on a Mamiya rb67 pro sd with a motorized back

I have looked everywhere, but I cannot find the procedure for taking a photo with the mirror up.
On the motorized back there is a switch that can go to three positions. 1. To take a regular photos
2. LT
3. T/M Up
Not sure how to work the mirror up.
Thanks in advance for any help!

Rich

It's pretty clear, back should be set on T/M Up, then follow camera instructions all the same for MU operation.

MU on body is a two-step process, first lift mirror, second releases shutter. Double cable release does this in one push as there is off-set between the two. Same can be done with two separate cables.

Hate to say this, but the whole thing is clearly described in instructions for both, motorized back and camera manual.