Put on new rear calipers, pads and rear cables. Parking brake functions but does not really hold the vehicle. seems it needs some adjustment but I do not think there is an adjuster. I have two 2003 bonnevilles. One of them the parking brake pushes down very easy and works great. The one I did the work on the the pedal pushes down pretty hard and does not really hold the vehicle. i can tell it is puttng some force on the brakes. Do I need to bleed them better?

i think that car has the type that has drum style brakes inside the rear rotor. you should have someone use the brake and watch it to see if there is slack in the cable at rest, thats a indication of the cable needing adjustment. if not maybe there is a adjustment behind the rotor for the shoes