Thanks for all the response guys!
At this point, I sort of imagine that it would not neccesarily by chronological, but more divided up by subject or topic. It could almost be a series of essays that are grouped together by similar types.
The "Why" would be a big part of the book. I would include a fair amount of how to - er, maybe more of a how I did. I'm not looking at writing a how-to book, but I would include enough technical details to make it interesting, without being overwhelming.
I suppose that, for example, about the electric car, I would explain what components that I used, but that would really just lead into a story of how I ended up at a moving sale where a guy had a full-size electric forklift in his garage. Why did he have one there? well, let me tell you..... How did I get it OUT from the forklift? That was fun too....
The misadventures, the why, and a bit of how to.
The road-trip has commonly been used as a structure for books and films. Ever read Tom Sawyer? All that was was a road-trip (OK, river trip...) with episodic adventures as they go down the river.
My life has been a bit of a "trip" the last few years too!