It is done both ways... more important, mount position, too high above CG will unload front, too low will unload back.... Tether length.... position... chute size... speed it will be popped are all questions that should be answered....
Best idea... talk it over with the chute guy to get the chute and mount point tailored for the car, then decide where you will mount the can.... that will tell you if you need to go through or under for the mount.