mop93 said:
Usually strats have a HSH routing.
Since when?
SOME strats have the "bathtub" routing, in which case you can do it without routing, but most of the strats I've seen (and I've seen more than a few) are going to need some routing. If it is just electronics, then you can get a new pickguard and - assuming you are handy with a soldering iron - you can do it pretty easily. However, if you knew how to use a soldering iron, then you probably wouldn't be asking this question.
My advise is to take it to a good repair shop. This is particularly true if you are going to need to do any routing. Unless you are an experienced woodworker it is very easy to cause serious damage to the guitar, and even worse, to you.
As for sustain, the pickups have relatively little to do with the sustain. A stronger magnet will pull harder on the strings, thus lessening sustain, but only if you have them set to equal heights, which they probably won't be if it is setup right. Sustain is one of those things which is inherent to the design of a guitar, and if you are looking for more sustain you are going to get further with either a) a better amp - probably a tube amp with no master volume (but you won't make your neighbors very happy with that); and/or b) a new guitar. I don't see much reason to put money into something that isn't going to be what you want, myself. When it comes to sustain, trems are a bad thing, but if you need them, you need them; and you are usually going to want to look at a set neck or neck-thru design, though some of the really high end and very tightly machined (which rules out anything by Fender) bolt on necks sustain pretty damn nice. Sell your Strat to someone who wants it for what it can do, and find a guitar for youself that does what you need it to do.
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