Andy_Mac covered most of it, some extras/clarification:
SpecB has (non-specB has instead of):
6 speed manual only (5MT or 5speed auto)
18" alloys (17")
SpecB bilsteins (non-specB bilsteins, softer versions. Both use the same springs)
Aluminium suspension components - control arms (standard arms)
Aluminium, I think, pedals (standard plastic)
No rear-wiper blade. - I think all SpecB's do not have one (mine does not), LGTs do. Might be all post-facelift do not have them.
Moon roof/sun roof (unsure, maybe just an option but I'm pretty sure all SpecBs have one. standard LGT does not)
All post-facelift LGT's use the 2.5L (single scroll turbo) engine, pre-facelift LGTs use the 2.0L twin scroll.
All post-facelift LGTs use SI drive (at least I've never seen one without, maybe it can be factory removed).
Pretty sure all post-facelift LGTs use factory 5% tints on rear windows.
I believe all post-facelift have a Macintosh stereo.