Timothy Nathan did it in his Aztec a couple of years ago. Alright, not a SEP but a MEP and similar numbers to many SEPs.Maybe you are braver than him but just one tiny thing to bear in mind, in a SEP if you go down it will be almost certain death.
I would assume the proper north pole is very close to sea level (plus or minus a few thousand), considering it is made of frozen sea
There are no mountains there, that is for sure, the air will be nice and cold so density alt not a problem, and any SEP would be able to fly over it. On a nice day I imagine it would be very pleasant flying, smooth, good viz...