I recently broke the lens glass of the convex mirror in the side combination mirror in the above vehicle owned by an acquaintance. He of course asked me to repair it. At first I obtained an adhesive stick on replacement glass (RockAuto GM1323920/GM1323B56) but he said it wasn't acceptable as he was concerned the adhesive would fail. He asked me to replace the individual convex mirror with the housing that it was attached to, saying it could be obtained from a junkyard. So I ordered that from a salvager (actually the entire side mirror unit). Before it arrived, I went to a GMC dealer parts counter to see how the convex mirror went into the entire unit. It appeared to go in by a single screw. Well when the entire unit came in from the junkyard, I couldn't find where that screw could be holding in the convex mirror. Can anyone here offer any assistance on how I can remove the individual convex mirror from the side combination mirror unit? The GMC Savana van is a clone of the Chevy Express.

Oh well.

Sorry nobody ever got around to helping you, I have no experience with Savannah'*.
Hopefully somebody will see this post and be able to help you.