No, there is no danger when removing the coils, as long as the car is not on.
The way to determine if bad ignition coils are causing your misfire codes is to swap coils on cylinders that are misfiring to cylinders that are not. In your case, you might swap the coils on cylinders 3 & 4, and on cylinders 7 & 8. Then start the car, and check the codes again. If the codes now indicate misfire on cylinders 3 & 7, then you know the coils are faulty.