Re: what pickup for neck ???
you'll be pleasantly surprised with the jb in the neck. i had it in a greco v with the invader bridge. the lowered bass and bumped up high mids of the jb suited the neck position (read more lows, low mids with less highs) perfectly for warm fluid leads.
cleans do suffer a bit especially with tube amps with low headroom but there's nothing a roll of the volume knob can't solve. also, the jb sounds almost single coil-like in the neck position when split.
fwiw, do spend a little time on adjusting the neck pickup's height especially using high output humbuckers in the neck.