I can see where you're coming from Rod. The engineering's simple enough in theory & as most cars are front wheel drive these days there'd be no end of donor possibilities. As others have said though, it's the styling of these sort of "out of the box thinking" trikes that usually lets them down. Some swoopy fill-in panels between the "bike" frame & car body would help a lot. (I'm thinking Testerossa style finned panels?).
Yep , fill them in with engraved / painted panels showing different engines .
You could have a different engine look every day
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