Im going to be buying a catback exhaust system and I want to install it with a few other friends and I was wondering how difficult the job would be? As far as I understand the only bolts that I would have to remove are the ones connecting the y-pipe to the cats. are those 14mm?

Any tips and help would be appreciated

 

Depends on how many years of rust you have there.

 

My question is: What is the size of those studs (bolts?) connecting the flex pipes to the test pipes.

as far as i understand other than the hangers thats the only thing connecting the catback exhaust to the car