I can attest to the utility of the method proposed by equill. It has the least propensity to marr the case's seam-edges, damage the contents of the case, or go horribly wrong as the Mac bounces off the floor. There is only one more convenient and effective opening method: use of a case-cracker.

Prior openings have little bearing on the ease of re-opening, which depends on the tightness of the screws in their holes. Don't overtighten when you reassemble, and the following time will be easier.

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