Ken, my old 4/4 was 1999 so it's probably the same set up as yours.
The spanner is meant to be hammered and there is enough room to swing a lead or copper mallet if you're careful.
When I took mine off for the first time, I was surprised how hard I had to hit the spanner and how many times to loosen the nut but eventually it did succumb.
Don't forget the nuts are handed so check the direction.
