If you're new to Seiko modding, Hands of Time: A Watchmaker's History by Rebecca Struthers might be worth picking up before you order your first bezel or dial. It won't teach you how to swap a chapter ring. It'll give you some sense of why the watch on your wrist works the way it does, and that context can make the parts you install afterward mean a little more. A few other reads below cover different angles, in case one fits better than another.
Why reading before you build might help
You don't need to read a single page to swap an SKX007 bezel insert. Plenty of people jump straight in with a screwdriver and a YouTube tutorial, and that's a perfectly fine way to learn. But modding tends to get more interesting once you understand a bit more about what you're actually changing. Knowing why the NH35 movement exists, why dial feet sit where they do, or what a "GMT" complication is actually doing can turn a parts swap into a build you can talk about with some substance. Worth a look if that sounds like your kind of rabbit hole.
5 books worth considering
1. Hands of Time: A Watchmaker's History — Rebecca Struthers
Struthers became the first watchmaker in British history to earn a PhD in horology, and this book is her walk through timekeeping from the earliest tools humans used to track time up through today's watches. It's not a repair manual or a parts guide. It's a history told by someone who actually builds and restores watches for a living, which keeps the technical details accurate even when the writing stays approachable. A reasonable place to start if the "why" interests you more than the "how," at least at first.
Many public libraries carry it as an ebook or audiobook through OverDrive (the Libby app) — Singapore's National Library Board is one example, though availability depends on your own library's collection.
2. The Watch, Thoroughly Revised — Gene Stone and Stephen Pulvirent
This is a decent book to hand someone who just discovered mechanical watches exist and wants to know what all the fuss is about. It covers how a mechanical movement works and what makes different watches notable, without talking down to beginners or boring the people who already know the basics. Handy for building a working vocabulary before you start reading part listings that assume you already know what a chapter ring or a crown tube is.
Available on OverDrive through participating libraries.
3. A Man & His Watch — Matt Hranek
Where the other books lean on mechanics or history, this one is more about why watches matter to people. Hranek collected 76 stories from watch owners, including some genuinely well-known timepieces, and the book reads fast because it's built around the people, not the specs. If you're modding partly because you want a watch with a story attached to it, this one might resonate.
Available on OverDrive through participating libraries, like Singapore's National Library Board.
4. Practical Watch Repairing — Donald de Carle
This one assumes you know nothing about watch mechanics and builds from there, which could make it a useful next step once you're curious about what's actually happening inside a movement rather than just what's visible from the outside. It's older and it's a repair manual rather than a modding guide, so not everything applies directly to snapping in an NH35 or 4R35 movement. But understanding how a watch gets serviced tends to make people more careful builders.
Available on Overdrive through participating libraries, including Singapore's National Library Board.
5. The Wristwatch Handbook — Ryan Schmidt
More of a reference book than something you read cover to cover. It breaks down how a mechanical watch works in the first half, then walks through different complications in the second. Useful for looking things up as you go: what a GMT hand actually tracks, how a chronograph pusher engages, that kind of thing. Could come in handy once you start looking at movements like the NH34 and wondering what the fourth hand is for. We couldn't confirm this one is currently on OverDrive, so it may be a used-copy or new-purchase find instead.
Putting any of this to use
No need to read all five before ordering a single part, or any of them at all. If the story side appeals to you, Hands of Time or A Man & His Watch might be the better starting point. If you'd rather get grounded in the mechanics first, The Watch, Thoroughly Revised could be the more useful read. Once you're a few chapters in and curious about what's happening under the caseback, that's a reasonable time to pick up Practical Watch Repairing or start flipping through The Wristwatch Handbook as a reference.
FAQ
Do I need to understand how a watch works to mod one? Not really. Plenty of modders start with zero mechanical background and pick things up as they go. That said, understanding the basics, covered in The Watch, Thoroughly Revised, can help with parts compatibility decisions and avoiding mistakes that come from not knowing what you're actually changing.
Is Hands of Time a technical watchmaking manual? No. It's a history book written by a trained watchmaker, so the technical details hold up, but it's built for general readers rather than as a repair or modding manual. For the hands-on mechanics, Practical Watch Repairing or The Wristwatch Handbook might be better fits.
Where should I start building if I want to put any of this into practice? The Start a Mod collection is a good place to browse compatible parts by movement, or take a look at the Project MM1 Pioneer Edition for a sense of what a finished build looks like.