You know, I was going to make a very similar post myself! What got me started was the Southwest Airlines 30th anniversary feature in the July issue of Airways (?). The picture with the flight attendants in miniskirts and hotpants looks to be taken on integral airstairs (yeah I know it's sad that I noticed the stairs that hot panted ladies were standing on), while the photo on the opposite page of the newly delivered 73G does not seem to have the hatch for them. Oddly, in the same issue, there is a pictorial about 4 717s delivered on the same day to TWA. These DO seem to have them. I guess they were eliminated to save weight, but I am unsure if they are still optional.