Absolutely Install them.Weld in units are the best.But Bolt in ones are better than nothing.I have a 68 barracuda vert, 318 auto car. freshly restored.Frame connectors make the car feel more solid,less vibration,The big plus is no worry about the body panels moving/flexing.Gaps should stay the same as assembled.The best bolt in ones That I see would be the ones from unlawful racing.More expensive than weld-in ones.But nice alternative if you don't want to alter an original car.I did the bolt in ones for that reason.My car has all original metal,I wanted the option to remove them.After driving the car after install,I should have welded them in.I'm not removing them.Car feels that much better with them. http://www.unlawfulracing.com/5.html