i just got a jdm header with a 2.5" collector and my test pipe for it wont be in till next week but i want to install it this weekend for the races. is there any way that i can put it on and have it connected to the stock cat. i know the cat is like 2.0" or 2.25" but if i rig something up so it wont be loud or should i just wait till the testpipe comes in??? i was thinking like connecting with a piece of high heat tube and some clamps????