Switching the CTRL and SHIFT keys around for object selection

When selecting objects, I’m accustomed to using CTRL to add objects to my selection set, and SHIFT to remove objects from my selection set. Is there any way to switch these around in Rhino?

I’ve just reached the MACRO part of the 2nd training manual (whoever wrote these training manuals is brilliant, they are very effective). I have a feeling the solution might be right under my nose, but being a bit of a newb…

Thanks all!

Hi Keith - nope- that one is not customizable.