This might help a little it was a write up I did a while back
I also have the Vibrant exhaust system and everything Mr. Digger is saying is accurate. Some of the problems I incountered are; stock exhaust removal, two of the bolts were fused to the flange so I tried to dremel of the nut and ended up going through my 3 discs with no luck. So I decided to use the hack saw and cut the piping which took a little bit but it worked good. Just make sure that you cut on a straight piece not on a bend so a collar could be welded on IF you ever have to use the stock exhaust again. After the stock exhaust is out I bolted up the downpipe, and yes I used the bench grinder to grind down the collars on the stock S/J-Pipe bolts. The Piping on the Vibrant J-pipe is to big so grinding is a must. Next I bolted up the catback section which is really easy, use the Kartboy exhaust hangers(buy them in advance,you'll need them.) That's pretty much it, I did not extend the O2 wire myself I took it to a local shop and they did a cleaner job than I could have done cost $80.00 but that's cool.
Things I noticed after install; RATTLING, I had rattle coming from the muffler hitting this metal lip that is located, well right above the where the muffler would rest, I fixed this by putting a peice of foam in between the metal lip and muffler, seems to be working good. The next rattle I had was from when I installed the Kartboy shifter, it was hitting the heat shield, so I just bent the heat shield away from the shifter, all is good there. Finally the last rattle I noticed was in the cabin and coming from the rear deck where the fux speakers are, This can be solved by removing the plastic section and putting weather stripping in between the plastic and the metal. I used 7/16" weather stripping and it works good.
All said and done I would still buy this exhaust system, I wish I would have been more prepared but it's not something that's to difficult to handle though.The sound is a low pur at idle and a deep growl at WOT I guess is the best way to decribe it. I did notice a lot more pull from 4k rpms and up. If anyone has any questions feel free to PM me also. And for those getting in on the GB you won't regret it, it's an awsome exhaust system!!!!!!!!
Edit: Alright, screw the foam, just grab a pair of channel locks and bend the metal lip away from the muffler, works a lot better than the foam idea.