Make the rail for the legs, just going with a single 1 x 4 as it should give enough strength.
Cut the ends to fit the mortises in the legs.
Make a couple of wedges for a tusk tenon.
Cut the mortises for the wedges, cut back behind the line so there is a gap and the wedge pulls the joint tight.
And that is rock solid, so call it done.
Flatten the ends of the top, if it was made out of decent hardwood I’d have put endcaps on for the look, but it won’t add any structural advantage so I’ll skip it on this.
I’m using 3/4 wooden screws to fix the top, so make 4 nuts and bolts.
Drill the holes in the legs and fit the bolts.
Grab another chunk of willow and make the nuts.
Test fit Better fix those dowel holes I drilled in the wrong place. Chisel mortises where the holes are. And patch. Then just plane them flat
Drill some dog holes, the cheap orange clamping squares are ideal to give a visual reference around the drill bit so the hole is at 90 degrees. The hole in the wagon is angled a couple of degrees so the dogs don’t push the workpiece up.
Make some feet for the legs. Bit of 1x4 will do for 1 side, oak for the other as I'll need to make the adjustable feet using the rest of the screw I cut. After planing all that spruce, it's a relief to be planing the end grain of some nice clean oak, much easier. Drill the holes And tap them. Make the handles for the adjustable feet
