help with extending corners on 3D multi-vertex parts

help with extending corners on 3D multi-vertex parts

dear Yorik, do you have any idea were can I find any help or guidance to do this extensio to make a 45 degree corner with 2 multi-vertex objects? I have no experience in Python scripts to do that...

picture is here...

www.miniwatt.info/test_freecad.PNG

Thank you!!

Lima...