That is important when you install those strips. Making sure the metal surfaces are free of rust and any old glue. You lucked out that you didn't find any rust on the T-bar. That's an area in particular that a lot of people have gotten disgusted with their car after the removal of old weatherstripping. You think you have a solid car to start, rip off the old strips, then BANGO! There's rust staring at ya! Not fun.
What is fun is when you get stuff done to it that makes it seem that much closer. Am I right, or am I right? LOL!