Remove Lower Motor Mount 3.0 litre Maxima
 

I am trying to remove the motor mount on the bottom of a 87 Nissan Maxima 3.0 motor. I cannot get a wrench to fit it well enough to turn it. Tried both metric and sae. Is this a special custom nut and bolt? I have tried 14mm and 9/16 6 point as well as 12 point, open end as well as socket. I need to replace the gasket on the oil pan and have to remove the lower mount to get access to the oil pan.

Any help?

Thanks,

Craigibc