I used a 1.2m 3/4" breaker bar last time I took a hub nut off and still struggled. I had to use a pole to extend it and get my son to join me swinging on it.
Do you really need to remove the hub nut if replacing a CV joint. I'm pretty sure last time I replaced a gator I just took out the long lower bolt and swung the hub and strut out until the CV joint popped out.

didn't bring many tools with me to Spain so think a trip to the local garage might be best.

They may hang on to your car until you give them Gibraltar...