Re-wrap in the packaging and don't say anything at all. Chances are he won't notice anyway; he'll be too busy looking for the Christmas wrapping paper. sellotape etc. Hope it's something you like!
Not sure what "Answer on a postcard" means. Hope this is ok. I agree with Theexwife. If I didn't want my wife to discover a present, I certainly would not have it delivered to our house among all the other things she orders. And, if I did, shame on me.
Long story short, so many deliveries for Christmas at the mo. I simply assume they are as I ordered so open them ready to gift wrap. Simple, or so I thought ....... DH abroad until the 23rd. and never, ever in the last 40 odd years has he bought any presents for family etc. , my job, so happily opened the last arrival. Oh shit, it is obviously his gift to me !! Answers on a postcard please !