Is there any chance you can give us a quick rundown of the filler neck replacement procedure? I've got one I need to replace and I know a shop would want to charge me for many hours of work where you say you're doing them in 35 minutes.
It won't take YOU 35 minutes, probably more like an hour and a half to two hours if you've never done it, but its not a very difficult job, and only requires basic hand tools.
Get the back end of the car up on jack stands. Remove the right rear wheel so you have some space to work.
Open the filler door and remove the 3 screws around the filler cap. These are the ones Ivan is talking about drilling out. Sometimes they're rusted pretty bad.
Remove the 3 or 4 10mm bolts from the plastic cover on the filler tube (they will probably just snap off), then rip the cover off and throw it away.
Remove the 10mm bolts that secure the filler to the body. One is near the top, and I want to say there is another near the bottom but I don't remember exactly.
Loosen the hose clamps on the bottom of the filler and the small hose that's next to it. Use a pick or small screwdriver to break the hoses loose by sticking the tool between the hose and pipe and working it around the pipe.
There is a plastic clip thing on the small hose that takes some fiddling to get it popped loose, then the small hose slides out of the frame.
Then work the filler tube around a bit and it pops out of the hose.
Once its out swap the small tube onto your replacement if it didnt come with a new one.
If you have the style with the valve at the top there are two small hoses to deal with but they're usually pretty easy.
Install in reverse of removal. Use petroleum jelly on the ends of the new pipe to make it easier to slide into the hoses.