Rare for a Reliant 3-wheeler is an engine that you can get to easily. In fact in this vehicle you can just sit inside and work on the engine.
The driver’s seat looks like an old school chair. It does have a cushion but if my brother used it, his head would have been poking through the roof as the extra height would have been too much.
Not the sort of sight you want to see if you are a rabbit sitting in the middle of the road!