PSE 9 help... quick question

I'm trying to put someone's face from picture A and put it in a box in picture B.

I've deleted the middle solid portion of the box on B, and I've cut/cropped the face from picture A. I just can't remember how to get B to be the frame for A and I can't find the instructions I used a few months ago.

Thanks

Nevermind, I got it  

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