Special Top-Secret Cryptic

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Across
  1. 4. companion in fling rider (10)
  2. 6. One addressed individually in letter (3)
Down
  1. 1. Power of determination (4)
  2. 2. XOR without the tail, Arithmetic Logic Unit, Rearranged (6)
  3. 3. Exist as honey's partner (2)
  4. 5. The possessive start of a surprise (2)