fiberglass door panels

Im starting to plan out my door panels for my 98 cherokee limited. Im wondering how to do it and will the fiberglass still to the arm rest on the door panel and the plastic of the door panel itself, because i do not plan to fiberglass the entire door, I want to fiberglass the bottom three quarters to where the armrest and window/lock controls are

If you cover the section you want to fiberglass with masking tape you can glass a moulded piece that won't stick to your door panel. Once it's set you can take it off and build up your pod on that. Then you can simply attach the pod to the door trim from the back.