referring to the shop part... if they are rusted you will need heat. if they are super rusted you will probably need to cut them off... I just did my JBA myself and had this issue. Cutting wheel to cut off the nuts/studs, remove the exhaust, recut the leftover studs and grind to flat... then redrill 4 holes in the cat flanges. Youll need to go small to big when drilling. it sucked....thinking about getting this exact exhaust. How tough was the install? I'm considering having a shop do it, partly cuz most of my bolts are rusted to hell (thats what I get for getting a 7 year old truck...). How much did you pay for yours?