Tips for replacing intake manifold/headers

I do not want to snap any of the manifold studs when I remove them. Fortunately for me, the engine was replaced with a remanufactured unit in 2009. But, the studs look like they are the original. So, if I lock 2 nuts together onto the stud, this would be the best way to do the job? I certainly do not want to use vise grips if I can help it because they tend to strip the threads and if 1 stud refuses to come out, I may just leave it alone