suspended ceiling

I want to install a drop ceiling in a basement bedroom, but because of heating/cold air return ducts, I need to have two levels of ceiling. How do I do this? I would prefer to have the same type of ceiling throughout, rather than drywall the lower section. Any ideas?

 

Here's my current plan for a project I'm working on next month.



....Use 3 1/2 inch screws through the adjustable wire cables available at HDepot to hang the grids perpendicular to the vents to the joists/ on the outside edge of the vents/ connect a main grid parrellel to the to the perpendicular main grids with rivets. Rivet on a wall grid to the parrellell main grid so it will create a channell to place a vertical tile........ Attach a two by four on edge to the joists at the top of the vents. This will serve as a support for the top of the vertical tiles...

install all the tiles under the vents. run the 3 1/2" screws up so the ceiling is tight to the vents......Place in the first vertical tile and use a rivet to secure a cross tee next to it and so on. .....You may need to first trim the rear top of the cross T's so they will sit against the tile. Slip wall moldings over the edge tiles. Secure a string across the top to hold it all together while builidng.......After the tiles are up.....Secure a wall molding at the top of the vertical tiles to the 2*4 on edge.......