* GX lib has no trimmings such as side skirt "sports pack", steel rims with hub caps, normally no spoiler, 2.0ltr, SOHC
* RX has different center console, fairly sure it includes climate control. Tarted up exterior, 2.5ltr (should be stamped on the block some place). DOCH if I'm not mistaken
* heritage is essentially an RX auto with leather
* b4, well, its a b4

2002 I think will have it as a Rev D which also has the "face lift" front. Bonnet and headlights are slightly different.

Some places you might get a bit of extra info on Libs
www.subyclub.com - anything
www.ozliberty.com - gen3 and gen2 heavy
club.liberty.asn.au (i think) - gen4 heavy
and to a less extent for the gen3 www.rslibertyclub.org/fourms (mostly RS's)


Happy to be corrected, not 100% on all of the above