If you're within the axle weights and the tire weights I wouldn't be too concerned about 100 or even 250 pounds. Just be aware you're over so you will maintain and drive the vehicle like you're over. That is, use good quality parts, particularly brakes. Don't go too fast, leave a long time to stop, etc.
Overloading any vehicle isn't a good idea but the reality is that it happens all day every day with very few consequences.
In the construction industry most people don't bother to weigh their work trucks. They load up the tools, supplies, and crew they need for the job and head out. I've seen many 1500 and larger trucks on job sites that are clearly overloaded and they pretty much stay that way.
Truck camper owner's were mentioned. I'm one. My truck's GVWR is 11,400. Loaded with the family, camper, and gear the rig weighs about 13,000. It drives well and has for thousands of miles. However, I'm not over my axle or tire ratings and I keep the truck meticulously maintained. I drive the speed limit or under.
I would much rather not be overloaded but I'm already driving a dually. The next truck will hopefully be a 4500 or 5500 series with a flatbed.
