catalytic converters

does a 1977 gmc seirra need catalytic converters to pass inspection or did it come with them my friend said if u buy a truck that didnt have cats on it u didnt have to put them on

That all depends on your local laws. According to the federal laws if it came with cats it needs to have them. If you have to do emission tests there it probably won't pass with out them.

yepp yours came with cats