Hello guys! I have a Fender Stratocaster made in Mexico and I want to make some modifications for better tuning stability. I am not looking to make any changes in the bridge but her is what I choose until now:

Schaller locking tuners

Roller nut

Roller string tree

What do you guys think?
As far as what you have that you are looking at, if the locking tuners are staggered then there really is no need for the string trees. The staggered tuners will pull the strings down. The roller nut is nice and could help but I am curious why you do not want to do anything about the bridge? If you are using a stock bridge/trem then this is where you need to drop the money. Put a top notch trem system on it and your tuning issues will be gone. There are several options to do this. Some with modifications but many are just drop in with no mods. I use the www.Callahamguitars.com trems and love them. They look stock except for the CG stamp on the saddles, the block is heavier and with locking tuners I never have to worry about tuning issues. I use the trem more than alot so this could be an issue without a good trem. I have just recently heard about the Supervee. This is a Floyd Rose type drop in trem system. They are pricey but everything I have read is good reviews.
Back to the string trees, if you just want to use them then I would just use one for the high E and B string, but again they are not needed with STAGGERED locking tuners.
As far as the nut, if you need a new nut then sure why not upgrade but again I would deal with the trem and the tuners first. Good luck

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