I for decades have had Defender 110s and for the last 14 years a Disco3-4, where I have used a plank with three and in later years two fork clamps screwed to it in the fashion of this link:
Being an engineer with access to a comprehensive workshop I made my own clamps that featured proprietary "quick release" skewers, though these days there are several of these ready made. For the last two years I use the system for an electric bike, and just as with my road bikes it works just fine.
In respect to suitable vehicles the cargo entrance height can be an issue with some high cross bar bikes and those where the saddle is not readily removable.
Minivan bike rack
A friend asked about our minivan bike rack so I thought the easiest way to describe it was on my cycling blog. The basic “model” would be...
williampedalson.blogspot.com
Being an engineer with access to a comprehensive workshop I made my own clamps that featured proprietary "quick release" skewers, though these days there are several of these ready made. For the last two years I use the system for an electric bike, and just as with my road bikes it works just fine.
In respect to suitable vehicles the cargo entrance height can be an issue with some high cross bar bikes and those where the saddle is not readily removable.