Halloween Treats

At One Stop Card and Crafts the theme this week is Halloween, which is sponsored by Tiffany Doodles and from whence these cute images come.
My hubby has a real taste for Cadbury's chocolate éclairs, so I thought I'd make him a little surprise!
The colouring is a little strange for an owl, but is Halloweeny and does match the sweets.
 The box was made with a template for a milk carton (2inch cube), which I made from card which I had printed with FSS purple pinstripe digi paper. After I had cut out the shape, I then sliced it through the middle, and used my Fiskars Threading Water  border punch to add the fancy edges. I chose this one because the pattern just fitted the dimensions of the box. I then cut and scored some acetate to fit inside to make a window and to make the box taller.
I had a few probs trying to find an adhesive which didn't show through the acetate (my double sided tape looked dreadful). In the end, after throwing away a couple of pieces I just had an overlap and only stuck the acetate to the card and not to itself... if you see what I mean.
Any suggestions for an invisible adhesive for acetate?
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