Purpose of Convertible Top Well Liner

Mine catches the leaves falling from the trees while parked. Are the shoulder belts for the front seats? I mounted them on the side panels after reinforcing them. That way it doesn't interfere with the top going up and down. Need Pictures?

My plan is to put shoulder belts in the back with an idea borrowed/stolen from a fellow forum member. In the front I'm thinking about putting in Sebring seats with the integrated seatbelt. Right now I'm in the information gathering stage.

Do you have pics of your setup?