H-Block... HELP...full size go-kart RC.

So what servo are you using? Were you able to modify it as shown in the video? What, if anything happens, when you try it? Does the servo move at all?

Personally I can't tell anything useful from that video so I'd guess that either you're using the wrong components or you've wired them wrong or you're not powering them correctly. Or perhaps the video missed out some essential information.

Steve