question for vintage Gurus/Snobs

Hand wound pick-ups versus mass produced pick-ups accounts for the majority of tonal diffrence. I don't see much diffrence in fit and finish. The wood is also a contributing factor. The best grade of mahogany (or other woods) that are used today would have been trashed back in the 50's. The timber available/used today by companys (some private luthiers still have a stock pile of the good stuff) is generally farmed, cut from younger trees or from the older stumps and just doesn't measure up tonally...
My .02 deposit -Pix

Huge subject Craig, first answer is that they are simply made differently. There are lots of little differences even on what are called 'reissue' guitars, sometimes great big differences.

On acoustics and archtops there is a wood ageing effect over the years, Yamaha are trying to recreate this with their L - ART series, new guitars that sound like old (in a good way). Necks are often improved as the they get played in (the neck on all guitars is a key resonant part). I also reckon part of the vintage vibe is pickup cores losing magnetism, thus giving a more subtle/milder vibe than when they were new.

Alot of this can be gotten either by careful choosing of your modern guitar or by custom spec or after sale modding. If you are new to electric you may not have formed tastes for certain pickups etc so have a good look around.

I am a bit of a vintage snob, I must admit. If you doubt the difference, play a 50's tele and a modern reissue back to back. You can't deny that those old guitars can play like butter and sound glorious. That said, I build guitars from modern parts or modifiy stock models to closely approximate the keys parts of that sound and feel. It can be done without tons of trouble.
One important part of the puzzle, after wood quality and pickups is the finish. After playing lacquer finished guitars for any length of time, modern poly finished guitars feel awful, plastic-y and cold. They sound muted and dead.

Is Fender going back to the nitrocellulose? Thats what they are advertising the highway one tele as. If its better, I don't see why they don't do it on all thier models.

Craig was asking about  what really affects the sound of a guitar, finish is a very small factor next to neck and pickups. Also with nitrocellulose expect your clean look to start looking tired in a few years, not a problem if you go for the relic mojo vibe. I think here the difference is 60s players who wanted a guitar to look good a long time (but were disappointed until poly came along) and todays buyers who will never play the newly nitro coated guitars that much (or in a smokey, sweaty club now we're smoke-free and aircon-ed).

Neck is crucial. If you offered me the choice between a 60s body and a 60s neck I'd take neck and bolt it onto a modern body every time. There's another key factor, often original Fender bolt-ons were a bit iffy but players shaved them, shimmed them until a great fit resulted. Likewise any guitar neck, nitro or poly, feels sticky/glossy to start with. Playing naturally smooths this finish and you get that 'like butter' effect. Some try and use steel wool but it's not as subtle. I suspect a nitro will wear in sooner and I'd look for a good satin finish in either.

All too easy to get hung-up on these visible signs and forget the pickups and wiring. Now here the truth is vintage controls did very little for the sound. Brian Setzer called the tone on his Grestch the 'mud dial' and let if fall inside the body. Most 60s Precision basses have a tone control that is horrible in the last half. Here modern pickups and pots give you more options. You can have hotter pickups than were ever available in the sixties or get subtle single coils just like the period. You just have to know what you want first.

I asked pretty much the same question to a Gibson rep. He told me that a person would manually wind the coils with a crank type wire winder and would sometimes get distracted or somehow lose count...that would create a unique wound coil with a different sound. Modern automated machines wind with exact accuracy...   I'm convinced that once someone knows the "formula" for a particular sounding pickup then it's simply a matter of programming in everything...I was also told that magnets will dimemish over time also affecting the sound...plus many other factors such as wood types, set up, strings, etc, etc....

I have always been told to never refinish a guitar. Only when the hairline cracks form in the origional finish does the fine wood tone begin to get out.
My 1960 Gibson 330 gets guitar polish a time or two a year but that's it.
Years ago a guitar sales guy tried to talk me into replacing my oh-so-mellow Gibson single wound pickups with Humbuckers. Good thing I was broke. Humbuckers are way too trebley for my taste.

Craig, refinish nitro is easier than poly, it comes off with chemical strippers. Poly finishes need a heat gun, it's a devil to sand off. Both stay in the wood grain potentially sabotaging a nice clean respray. You can buy unfinished routed bodies or you could even look at makers like Gordon Smith who offer uncoated guitars as an option.

However I think you're missing the point, body finish is a pretty minor factor overall. Pickups and neck first of all. You're also falling into the trap of aiming for an 'ultimate' guitar I think, when you should be looking to focus in on the exact kind of sound you want.