Do most pickups fit in most guitars

[Gilles]

Well question says it all... If I buy a pickup for my Squier Strat and I later buy another brand of guitar that has a single coil pickup, should it fit? Or sizes pretty much standard?

[Tarl]

Sizes are pretty much standard for singles, humbuckers and P90s. There are a few oddballs out there. Also some PUs are have F spaced pole pieces to accomodate the wider string spacing on Fender guitars.

[suttree]

yes, most single coils are the same size, the other common sizes/shapes are p-90 (two types), mini hums, full size humbuckers and telecaster types and etc. my point is that as long as it's apples to apples (strat clone single coil to strat clone single coil), you should be safe (although sometimes you will have to make minor modifications to fit).