Using a GEM for alt-az setting - how?

This is probably obvious but I can't figure it out.

I want to take some pictures of iridium flares, just for fun.
Maybe 2 minutes exposures to get some of the background stars too.
I also want to set up my equatorial mount and camera, pointing at the
correct alt-az well in advance (daytime).

Assumed starting settings;
Mount is set up well polar aligned.
RA is at zero deg. By this I mean the counter weight bar is pointing due
north. DEC is pointing due up/north.
I now set the setting circles to RA=0 and DEC=90.

How can I now convert the alt/az values I get from heavens-above so that I
can preset my mount to them using my setting circles? I strongly feel this
should be possible but may of course be wrong...

I'm using Linux and have Cartes du Ciel, Kstars, Celestia, and Stellarium
installed. They have some convert tools but I obviously can't use them or
they are not intended for this task.

All help and/or pointers much appreciated

I'm at app. 62 deg. north and 17 deg. east.

And Happy Easter to all...