But, the Kaiser Darrin has it beat in the "Dissappearing Door Department...and Well, almost...
You can get it in up to the door handle...and it goes sideways. but it more or less dissappears, and it's not half a door....and It's a '54. it's older than the Z1.
Pretty sweet stuff. I bet it could be perfected, it's pretty much the same as what you'd find on these elderly people transport vans because they were coming up with concept where the door is the ramp.