converting/replacing surround channels into stereo ?

Hello everyone,

is it possible to convert a surround channel in Nuendo into a stereo track - or replace it with a stereo track, taking over all inherent automation data ?

The situation is that i have an old project that was mixed in 5.1, which now needs to be stereo only. Re-routing to the new master out went fine, but i have lots of tracks feeding into the surrround group and reverb channels with automation, which would then be lost. Is there a way to do this or is the only option to downmix the surround channels via insert/plugin ?

Thanks in advance,