Is there a way to test the resistance of a glow plug without taking off the intake manifold and what not? What is the simplest way to achieve this process if I just want to test them to see if it needs to be done.

The reason I ask is that I am having a starting issue whether it is hot or cold and I am wondering if it is the glow plugs or not.

Edit: The car has 62000 on the clock and is a 99. So, another question is how long do those plugs last? TIA