Chosen Solution
Can I replace the harddrive on a mid 2012 core i7, 13” macbook pro with one from an early 2011, core i7, 13" macBook pro. I’m trying to save time by not having to transfer all my data to the other harddrive.
Sure you can, reset the PRAM after replacement and you should be done. In my experience however, it would be a good idea to run the final combo update update of the Os you have installed not to miss firmware updates and correct possible small glitches.