Aggreed, any competant workshop can work on your skyline. If its just maintenance your after there is no problem taking it to a reputable general service centre. if there is something you want them to take extra notice of or are unsure they will be familiar with, then make a note of it to them.
By the way, to the guy that said dont let an apprentice work on your car...Im an apprentice and if you have seen my thread you will know im currently rebuilding my GTR ground up!