I am adding a set of side pipes to my 65 Corvette. It was not an original side pipe car.

As such, this will require body cutting into the rocker panel at the front an rear wheel wells to accomplish this.

I was told that this is not a big task to do it correctly to NCRS standards. This was proposed to me to be done with the body ON the frame.

Someone else told me today that to install these pipes correctly the body will need to be taken OFF of the frame completely before cutting.

Which is correct? Can the side pipes be installed correctly without taking the body off of the frame?

As the side-pipes were also a dealer installed option I don't believe you had to alter the body. My Corvette specialties catalog lists the side pipe kit as having: Side pipes (hook up to the stock ram horn manifolds) mounting brackets, Repo metal rocker panel/pipe heat shield. Aprox. $1200. My Ecklers catalog had an economy set with fiberglass rocker/heat shields for about $900. They also had an excellent assortment of other exhaust options, including the real 4 into 1 snake-pit for big & small blocks. As the chassis didn't change much the C2 to the C3 that might be an option also. Unfortunately the Garage Monkeys seem to have misplaced my Ecklers catalog. They Have a good web site and their tech dept. are Corvette lovers and very helpful.