I have the 4 sections that make up the base walls(all new repo) and looking them over looking at my pump and pics on the net. I see the covers are not ment to go on the same. On my pump all panels fit on the Inside of top and bottom rings The repo parts the extension s fit on inside and the doors (one with hole one without) fit on the outside of the ring Have any of you used these parts with your original top/ bottom rings? How was the fit? Gap between doors and extensions? I have not looked Inside mine yet. But are the extensions and doors. 2 different heights?