Nice looking cars...too modern for me but I'm still tempted...
As noted, the wheels come assembled and painted or unassembled and unpainted:
Option A - Fully Assembled & decorated flatcar with wheel frame.
Painted wheel sets ready to be glued in-place.
$65 each.
Option B - Fully Assembled & decorated flatcar.
A 3D printed acrylic plastic one piece wheel frame,
and a sprue of wheel sets - requires removing from sprue,
painting and installing. Instructions inlcuded.
$45 each.