I've got all of the finger tapping down perfectly except for the last part where Van Halen alternates between tapping 5 8 12 and 4 7 12.

How should I move my left hand between the two positions in order to do it the speed that he does?
the way i play it is by sliding. when you are tapping the 12th you should simultaneously slide 4/5 or 5/4. if you get this down perfectly then it shouldn't sound under the 12th. it is tricky to time however.
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