The pickup routing will be large enough to accommodate a single coil in the middle of it, if you can live with the empty space around the coil. That's the only thing you need to worry about. There is nothing in the wiring that should cause any trouble using a single coil instead of a humbucker.

However, if you think the current pickup is weak, I don't really see how using a single coil will fix this...

i agree, if you are looking for a stronger pickup at the neck, i would look for a higher output humbucker, a singlecoil is going to be the same or weaker than the one you currently have, even if it is a stacked humbucker. also, most of the time you will not want the twangier sound that comes from a singlecoil in a 7 sting... unless that is exactly what you are looking for. and as ibzRG just mentioned, if anything, the wiring will be even more simple, most or all singlecoils have only 2 conductor wiring, whereas humbuckers can have 4 or 5. if you go to seymourduncan.com they have wiring schematics that will basically show you any combination of pickups that you want to use. good luck. oh yeah, and if you go with the singlecoil at the neck and are able to adjust how close it is to the neck a bitwithin the body cavity, i would find out where the closest harmonic location is and place it under there, the tone seems to be better when a pickup poles are under a natural harmonic location. good luck!

A second thought just occurred to me.

Some pickups are designed to be screwed in the body and some are mounted with the pickguard or rings. The difference is the presence or not of threads in the mounting ears at the base of the pickup. Pickups that mount on the body have threadless holes and the mounting screws screw into the wood. Pickups that mount on rings and pickguards have threaded holes.

Using one type in place of the other is not the simplest thing to do, as it requires some McGyver-ing...

I had to change a single coil from mounting directly onto the body to mounting on a pickguard instead and the lack of threads in the mounting holes required my to use nuts.

Just a thing to keep in mind, especially when swapping across pickup types.

I always use two bridge humbucker pickups on my guitars. Replacing a humbucker with a single coil is going to sound weak. The reason I use two bridge pickups is that they are usually more powerful than a neck pickup. So when you mount one at the neck you get more sound picked up.

i agree with satan. hmm i never thought id be saying that. oh well. i dont thnik i would go for singles but im a little biast toward the humbuckers anyway. id suggest a nice hot duncan, but there are several brands that are good.

by the way, im not trying to be a smartass but if you think the thing is weak why didnt you buy something else? its pretty bad that you have only had it one day and you are already wanting to ditch your pickups.

if you are still interested in a single coil, go to the seymour duncan website to their custom shop area, they have single coils with humbucker covers.... it would fit perfect in your instrument.