gs exhaust?

i was looking at cat-back exhausts for a 1990 gs @ nopionline.com and noticed that most of the good brands (tanabe, greddy, dc, hks) only make products for the ls and rs but none mention the gs. well a few do but not most. are there any differences in the exhaust set-up between the trims? or did they just forget to put the gs on there because they only knew about the gs-r? (you never know!) i did a search but didn’t find anything mentioning differences at all. this may be because there aren’t any but i am not the type to make assumptions. any helpful replies are greatly appreciated. thanks

LS, RS, & GS are all the same. It’s just the options you get that are different. Unless it’s a 4 door in which case you might need an extender piece but my conscience (sp?) tells me there all the same… HTH

Dev