Having tried Simon's Appia for size I can report they work really well and that its a weird feeling being able to slide the whole bench back and forth so easily without it racking, snagging, jolting, snagging or (with those springs) needing to be hauled forwards as with just about every other car ever made.
I agree that the way that Appia seats slide is beautifully conceived and executed.
However, at the risk of being shot for saying so, there are (a few) other cars that are as beautifully made. My 1937 Terraplane is virtually all original inside and out except for the front mat, which had been replaced with a nasty acrylic fabric carpet. So last year I decided to replace it with one of the excellent reproductions that are available, and to do so I had to dismantle and remove the front seat, which slides back and forth as well as an Appia one, despite being much larger.
Pic attached. Everything in this picture except some of the (removable) accessories, the mat and the HORRID 80s temp gauge, which is shortly coming off and being replaced by an older one, is 78 years old and unrestored. And the seat frame is made of WOOD. And, ingeniously, it also pivots round in an arc to the right, as my car is a 2-door car and the seat swings round to allow better access to the rear. The reason it swings to the right is that for safety reasons Hudson designed left-hand-drive Terraplanes for right entry and exit (and vice-versa) - my US-made LHD car only has a lock on the right-hand door, the idea being that the driver slide across and get out on the passenger side. That's the kind of thinking and practice that Lancia would have approved of!
As I said above, sorry to mention this - I know I am not supposed to mention non-Lancias. But there ARE a few other nice marques - and in my defence the company that owns the Hudson brand is now the same as the one that owns the Lancia brand (Fiat...).
