cephus said:
All I can say is be careful drilling out the holes for the tuners.
Better advice would be to NOT use a drill. The right way to do it is with a reamer, but a good one would probably set you back more than the cost of getting it done by someone who already has one (like the guy who did your setup).
As which gears, you will find none better than Gotoh 510's. They are, without question, the best made gears on the market. They are quite a lot better than Grovers or Schallers, though they are both fine gears in their own right.
Most of the time, though, if you are having tuning problems it is not the tuners. It is more commonly a combination of things, including the nut (though if you've had you guitar setup by someone good, that shouldn't be an issue), trem issues from unbalanced string tension to the string binding in the bridge somewhere, to (most common of all) poor tuning or trem technique. (I never like to say that to customers, but sometimes it is just the way you play, and you need to either live with it or change something about how you play). First and foremost, make sure you ALWAYS tune up to the note (tuning down leads to slack on the post, plus you can get some spring back from loose fitting gears in the tuners, not to mention sticking in the nut).
The big question I would ask is this; do you actually use the trem; and if you do, do you mostly use it to go down in pitch, or do you need to be able to pull sharp? If you only ever use it to go flat, then it is relatively easy to block the trem so it will only go down. If you never use it at all, then just block it so it can't go anywhere. Either of these will insure tuning stability much faster than new gears or a new bridge.
It is unlikely that parts for a stock Fender will fit an `80s Squire directly, by the way. Most of them are made with metric measurements, so they don't match. That means you will probably be looking at having some holes filled and redrilled. Another possibility, though, is to keep the bridge which is on there and get replacement saddles for it from Graph Tech. The String Saver saddles really do work, from a string life and tuning stability point of view. If I was going to recommend just one mod to your guitar - well, if I was going to recommend just one, it would probably be new pickups, but other than that - it would be String Saver Saddles.
(By the by, I'm assuming from your desire to change the bridge and gears that you are having tuning problems. But then, you probably figured that out already.)
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