How do you get behind the glove box in a 1998 Blazer? I see there is one tab holding it but I feel like I could break it if I pull on it and I do not want to do that?

 

Unless the '98 model is different from my '02, you simply pull forward on the thick wire that the door latch is against that allows the entire glove box to rotate toward the floor.

It is a very light finger pull. If it requires anything more than that, then either it is different or something is blocking it. I think there are videos on Youtube that show this.