took more pics of it apart and some details
this pic shows that its hollow, i cut a hole out so you can get inside and you can cover it with the panel as shown on top
heres the bottom where the grip goes into
heres what a kit might look like i forgot to put in all the parts in there but its an idea of how many parts are in this
heres how the trigger will be put together, theres to slots on eachside that the trigger have a pair of holes that a pin well help it slide back and forth