muffler installation queston

i think i found what mufflers i want to get, there the dynomax ultra flo ss's and im going to havea muffler shop do the installation but i migh need to know who tall and wide y stock mufflers are so i can ge tthe right size i think but im not for sure. Does anyone know how wide the muffers on a stok gp gt are? And does anyone know if i have to worry about the size because the muffler shop can use adapter of some sort to instal them . thanks

My friend bought a Dynomax mufflers for his GTP that where for our cars. Try finding those.