On early upholstery, the seats have top support perches that extend out of the armrests. On a quality upholstery job, the leather is wrapped neatly around the perches, such that inner stuffing is not visible, and where weather cannot easily enter here. Is this opening in the leather a hole poked through it, or is the leather split and wrapped around the perch here?
I would think split, folded under, and wrapped around, all done as installing the covering. I did a T recently, and it would be difficult to punch a hole in just the right place, then thread the material out and over it.
Thank you David, this was my assumption as well, as I too am intent on doing this upholstery work myself. I have to believe it would be possible to have only a hole for this hardware, however I can understand why doing so would amount to a "one-shot" affair. I really need to get out and look at an original before taking this on.