Thank you Roland and others, it seems that Park2 could be the way to go for me.
In my case three things worries me:
-my latitude is 42 deg, but that it shouldn't be a problem
-my rings are not very quick to lock: I have to put on the half ring and tighten the screws
-the scope will be unbalanced in DEC without the imaging train and guide scope
Roland, Do you think the DEc friction will manage that unbalance for the time required to lock the rings?
or is this going to stress the mount too much?
I think I can find a balance point for this unloaded configuration, load the OTA in this configuration and slide the OTA back during final balance (it is a newton).
Thank you and
Happy New Year