What Is The Diff. Between 4dr Civic's ?

i waz wonderin wat is the difference between the 88-91 4dr civic's ? when i say this i mean 88-89 and 90-91. like the crx's and hb's have a few difference here and there but i wanna kno about the 4dr's. any help would be koo.

the bumpers/ bumper lights, tail lights, corner lights, door trim, and i think the dash is diff between the 88-89 and 90-91 4drs