Hi guys, first time posting here. I was wondering if anyone who knows more than I can help me with some fitment question I have for an aftermarket exhaust. I am looking to get an invidia q300 axleback quad tip exhaust. The thing is it is a RC350 Fitment. I know people have used this particular exhaust on their IS, but I cannot weld, so I am wondering if this fitment will work with standard exhaust brackets, or if I will have to take it to a shop. Is the only difference between the fitment of these two vehicles the fact that the stock "diffuser" won't fit a quad pipe? I intend to get a new diffuser if I get this quad pipe exhaust.

 

It will bolt right up with zero modifications required. The only update would be the one you stated, changing 14-16 diffuser to 17+ or quad aftermarket

 

Do you know of any diffusers that work well with angled exhaust? I don't want it to look weird with a diffuser that doesnt fit right.