well what would you say is the minimum Length X Width i could go?
i figured that may be too small, max height clearnence is 15" from the lip of the tray i plan to use to bottom of the light. my max width is 12" (this is from back wall to edge of shelf there is an extra 12" beyond the shelf to the closet door)and the other dimension is negotiable up to 74". So in sumation my full space is 74"X12"(24" if from wall to door)X15". any advice with these dimensions would be much appreciuated

(Alternate plan could use closet floor)