Ask and you shall receive.

Once upon a time air bags had removable reusable tops. Here is the bottom of one of those and the rubber bumper that is attached to it, that the bus comes to rest on when you dump all the air.
my bus 059.jpg

Somewhere after 95 but before 98 they increased the diameter to the air inlet from 3/8 to 3/4in
my bus 058.jpg

This is what happens when the Horners talk you into getting under their bus and you let Janice go unsupervised with the camera.
P1051033[2] (2).JPG
You have never done a really dirty job till you have had to rinse off with gasoline