Need help installing interlock cable with B&M hammer shifter!!!!!!!!

i'm installing my B&M hammer shifter and everything is going fine except for that stupid interlock cable crap!!!!! i'm thinking im not installing it right, i'm not sure. when the key is turned on, the key wont want to remove unless its in park. thats good. when the key is removed, it still lets me shift into all the gears.

what am i doing wrong?????????

should i have my foot on the brake while installing? does it matter if i have the emergency brake on? all steps and tips are really needed.

if anybody had installed one let me know how to do it.

thanks