I don't think there's anything more mysterious about swapping plugs on a Boxster than any other car or engine.
The coilpaks come off easily if you give them a slight twist as you pull.
But, consider that both the plug and the coilpak bolts are steel while the head is aluminum, meaning that you can strip the aluminum head far easier than you'd imagine! Ton$ of fun that!
So a proper torque wrench is essential. But how you gonna get a torque wrench on an offset Allen wrench?
Step up and make an investment into a proper set of hex bits -
. A set will cost $20 and with a ratchet and 6" extention will make the job much easier and not risk having to retap a stripped head. You'll end up using them for way more than you ever imagined.