if the exhaust is for a 2000-2001 GSR you'll be ok. The 2000-2001 GSR exhaust system is identical to the 1994-2001 LS exhaust system in length. However, if it's for a 1994-1999 GSR, the exhaust will be 2 in. too long for the LS.
BTW I must have answered this a million times already and posted it up on Superhonda, Hondavision, Honda-Tech, Interga-TypeR.com, Honda-Acura.net, Club Si, etc. and of course here over the years....it must be in the search function at all these websites...and yet here we are: another person who refuses to use a search function and wants a free handout without any effort...sorry if I sound pissed but being repetitious is boring to everyone here (not just me).