There is a guy on the WestCoast somewhere who refurbishes the 60's type ET-IIs. Very nice.I seem to remember in BC or Washington.
Narrowing the rear is not that pricey, and if I had a Dart, that is the first thing that I would do,cuz I love those old Ansens and ET-IIs. And I love the deep-dish look. And they came mostly, with zero or close to zero,off-sets. That means backspaces of about 4.5/4.75 on 8 to 8.5 wheels.
If you are into Rallys, Wheel-Vintiques can put the center nearly anywhere. I have two sets of theirs; a pair of 15x8 fronts with a 5on4" and a set of 15x10 rears with5on4.5". Both with custom bs's. I no longer run these.
As to spares? To me they are dead-weight, and I have never carried one. Even if I wanted to, it wouldn't fit in the stock well. The fronts are 25" tall and the rears are nearly 27"s, so to save the TracLoc, I'd have to carry a 27. Hmmmmmmmmmmm. I have had one flat in this car,since 1999;so I will continue to drive without a spare.
To tell you the truth, I haven't had to install a spare onto any of my cars since the 80's; which is the last time I was running junky tires cuz I was soooooo broke.
TB; sorry.
I misread your comment,as to the KHers.