Soil Loading System

Clamp the hopper mounting plate to the top of the main frame, positioned as shown, with the cutaways positioned by the leg holders.
Clamp it so that the side you grinded down the welds on is touching the main frame.
Torch the holes thru to the main frame.
Check that the fit is good by putting bolts in all the holes.
Grind away all the slag.
Bolt the mount to the frame.

Install the hopper supports into the leg holders.
Make sure you put the support with bolts on it on the correct side (refer to your shaker motor and look where you marked it.)
Their bottom side should be flush with the bottom of the leg holders on the frame.
Make sure they are orientated correctly. See photo.
On the side of the shaker motor that you didn't weld bolts for, put a bolt (3/4"x1.5") thru both holes and tighten nuts onto them.
The nut should be on the side of the mount that the motor will be installed to. (see photo)

Clamp the 34" tall hopper back to the hopper supports.
It should be centered horizontally between them, and touching the supports all the way down to the hopper mounting plate.
Torch through the holes circled in the diagram, so you torch through the hopper sheet metal.
Torch through it on each side, just enough so you have 2 small holes.
Un-clamp the sheet metal and torch 1/2" holes for the bolt.

Grind off the slag from the torching.
Mount the first plate back to the hopper supports.
Use a 1/2"x3" bolt and a nut with washers on each side.
Lift the side pieces and clamp them to the first plate via the hinge plates.
Minimize the gap between them as much as you can by pushing them together tightly.

Clamp the final piece in place to the other side of the side pieces.
Yet again, minimize the gap between the two.
You may need somebody to get inside of the hopper and push out so you can clamp it well.
Weld the last piece like you welded the first one.

Get a friend or two and lift the grate on top of the hopper.
The front end (with the slots) should be as shown, and the grate should be inside of the hopper on the other side (the side with the nuts).
Have your friend hold the grate in place for the next step, or use C-Clamps to clamp the grate to the supports.
Bolt the grate to the hopper supports (1/2"x 2.5" bolt and lock nut). Bolt both loosely, and then tighten them.
You'll need 2 washers on each side, as the holes are slots and a 1/2" washer will be too small to prevent the washer from warping. Use a 3/4" washer as the other one.
You may want to use a large nut in place of a washer on the hopper support side. (see photo)