Re: Trembucker in the neck.
Trembuckers are just a little wider, and in theory, lower in output compared to their comparable hum-spaced models, but it's so little it's not worth considering. This is because they have slightly higher resistance at the same number of turns, due to having more wire per turn on the slightly longer bobbins.
Pole spacing doesn't much matter anyhow; pickups work just fine with either spacing in either position, with the main differences being visual.
Many trem spaced pickups are no more ill matched to the strings at the neck position than are regular spaced pickups. In fact, some might fit the neck string spacing better than a regular spaced humbucker, especially when you have a wider nut than the norm. DiMarzio recommends F spaced pickups in the neck position when the string spacing calls for it. (That said, DiMarzio F spacing – and regular spacing – are just a little narrower than most companies' equivalent spacings).
Regular spaced bridge position humbuckers are a bad fit to string spacing in most modern Gibsons. Modern Gibsons ideally have a 2 1/16" pole spacing for the bridge pickups. But you don't see manufacturers pushing, and people rushing to install, Trembuckers and F spaced pickups in the bridges of their LPs and SGs and 335s...and they sound fine even with a pretty bad pole piece alignment with the strings in the bridge position.
In short, don't even think twice about it. Put any pickup in any position, use your ears instead of your eyes, and you almost certainly won't have a complaint.
