Spirit System

I know the Spirit can be mounted sideway on top, and still fly right, just have to move the servo connectors accordingly. But will rescue work as expected if it's mounted sideways? Due to a better solution for cabling, I'd very much like to mount it sideways...

Yes, it will work in the same way.
It has to be mounted just perpendicular to all axes.

Nice.

I have mounted the Spirit sideways now (connections to the left) and tried to get the Spirit to work correctly for the last hour, but I'm just not able to get it to compensate correctly. Anyhow I adjust the parameters and connectors, it will work two only servos in the x-axis, and all three in the y-axis. As far as I have figured out, the Spirit must know it's mounted sideways to work correctly. Or am I missing something significant here?

You have to just select Vertical position and check according Reverse box in the Sensor tab. Nothing more is needed if you are switching from normal position (servo movement was adjusted previously).

Just to be sure we understand each other now. The gyro is still mounted in a horizontal position, but it is turned 90 degrees counter clockwise, with the connector pins to the left side. And the solution is to tell the Spirit it is mounted in a vertical position, even though it is still mounted horizontally?

Ah, sorry I have misunderstood you.

Unfortunately this position is not officially supported, but you can use workaround so that you will set 90° virtual phase angle offset.
You can find the parameter in the Expert settings.

Thanks. I'll try again later today.

The procedure is to set up the Spirit the regular way, then turn the Spirit 90 degrees counter clockwise and adjust phase angle accordingly?