Yep and yep
Thanks for the responses.
The best way is to open from the bottom which is what I was trying all along.
The selophane is sealed on boththe bottom AND the side of the bottom. You just can't get the side bits undone so I eventually cut across with a modelling knife and then undid the fold over bits on the bottom. 3rd attempt and 5th attempts lucky as I needed to prep 2 decks.
Once I took the deck out, you have to be carefull opening the lid so that the flap doesn;t drease on the front of the box. Took out the cards and replaced - one with a stacked deck and another with an ID.
I had some new box seals which I used before putting back into the selophane. To finish off, I re-folded the bottom bits of the selophane and glued back down with a Prit stick.
You can't tell them from new

Member of the Magic Circle & The 2009 British Isles Close-Up Magician of the Year
It's not really an optical illusion - it just looks like one!