1) Best way to secure ply top (overhanging style) to side panels.
I like to put slot half in at top opf side and back panels and use either metal clips or make the groove wider and make wood clips.
>2) Best joinery for side to back panel
If you are fastening frame to frame, then you can dowel, beadLock, M &T or run tongue and groove the entire length. Both pieces are in same direction so no problem there. You might also want to make corner posts (1 1/2" square or so).
>3) Should back panel's lower edge be at same height as bottom of drawer box?
Yes - bottom is bottom.
4) Should the back panel be joined to right panel, or left face of >drawer box. >
You might want to get a set of plans...not to use but to use methods...like Norm's desk plan.
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