Are the little clips on the fuel rail connecting to the injectors really all that important?

 

Yes; otherwise the pressure will blow the rail off or there is the possibility of a leak where the injector and fuel rail meet.

Remember -- Detroit doesn't install anything that *isn't* important, no matter what any so-called mechanic may tell you. A manufacturer doesn't want to spend any more than necessary when building a product.

 

Stupid question #2: is there a secret way to get the fuel injectors to seal to the manifold, or am I just an idiot

 

Hopefully, you replaced the O-Rings, and when doing so they were lubricated with a light coat of oil and rolled into place. If not, they'll tear. The O-rings should also be lightly lubricated when installing them onto the intake for the same reason -- to prevent tearing.

 

Did so, and still leaking.
I'll try replacing again though

 

Sometimes they have to be pushed until you feel some type of feedback where you can tell they've seated. Visually inspect each ring for any damage, and if they aren't just lubricate them and install them one at a time.

 

Against popular assumption there only used to remove the fuel rail and injectors all in one otherwise an injector can get stuck in the intake pulling the injector out off the rail and gas will pour out. The fuel rail bolts (4 bolts) holds the assembly down and secure. Look at some aluminum rails they dont use clips as the o rings are a very tight fit and the injector will not come flying off or leak from the pressure because the rail is bolted to the manifold........