Ok so I ordered my Jdm Itr header and was wondering if you guys think I should buy the upper and lower heatshields for it. Are they really necessary? Also, I ordered a new 2.5" carsound cat to fit the header, once i get my rsr exmag catback which i believe is 2.36", how is it going to bolt on to the 2.5" carsound cat? Is a muffler shop going to have to weld on a smaller flange to the cat?
Thanks in advance