Can't look at the picture, get all kinds of spam, spyware, popup and virus warnings when I try and look at a imageshack hosted image.....
Please use something other than imageshack to host these pics....
There is a small sloted plug that you remove and that is where the sensor goes. you might have to heat the carb up with a heat gon to get it to come out. (be careful if there has been fuel in there)