i have 99 gsr rear trailing arms complete with gsr rear disk breaks on my 99 civic ex, the whole trailing arm bolt right in with no hassle, the only problem i ran into is you have to do some modifying of the E-brake cable to get it to fit right. other than that i also added the civic si brake master cylinder. the swap was easy and took a few hours.

my opinion, well worth it. not only does it make your car look better with rims. but also breaking was really improved. some steel braided break lines would help alot more also.