I'm not sure if this is the part # I need, I need an electronic speed sensor for an '88 firebird. I don't want to order the wrong one, in the book it looked to be right, it has an extension that you can see in the picture and the other 2 don't. It's also the cheaper of the three, I figured one for an auto would be more. He couldn't look up the part for a manual trans, he said there was no way to differentiate in the computer. thanks