Here is a picture of mine(`36 Buick 40 series), the lower piece with the arm that attaches to the vac. motor, is inside under the dash. Upper part is outside, they sandwich together with the 2 screws, body sheet metal and gasket are in between. There is another type, second picture(probably what yours are), this one needs some type of lower inside bracket, i don`t have it to show. I have a friend that has this type, and will see if i can get a picture.