Flowtech Header Install Trouble

[97 cobra581]

I own a 97 cobra and have my car in the shop right now trying to install flowtech 12114 headers into my car. First glance the mechanic told me the new motor mounts and headers will be done within a week. Then told me the passenger side header was hitting the frame before the engine even touched the engine mount. So i called and flowtech said that the headers i have are the right size. The solid motor mounts claimed they were for a mustang gt of the same year but was told it was the same size as the cobra? so i dont know if my frame is messed up or if the mount are the wrong size? any help or comments appreciated!!