I went to Lowes and bought a few supplies that I would need.
-1 8"x24" piece of galvanized pipe that is split down the length
-1 new 5 gallon bucket and a lid that fit securely
-1 2 piece of 2" PVC
-2 2" plumbing couplings
-1 8x2 1/2" Shop Vac hose
-1 syringe of 1 min epoxy
-A small amount of self tapping metal screws
-1 tube of caulk
We sat down and he came up with pattern that I could lay out on my piece of sheet metal and just cut out my funnel. To do this he used all sorts of math from college that I have forgotten and some odd formulas. In a few minutes we were drawing the cut pattern onto the sheet metal. When I put the cut piece of metal to the test and fastened it together it came out perfect! No cutting necessary. When you screw the funnel together its best to predrill holes in the overlapping piece so that the screws will pull the underside piece tight.
(I will come back and post the dimensions and figures at a later date so that everyone can do this the easy way.)
Next I had to cut a whole in the funnel so that a piece of 2" PVC could be inserted at an angle. This wasnt very difficult, I just held the piece of pipe above the funnel and drew what looked like the correct cut on the pipe then whacked it off on the band saw. It really doesnt have to be perfect I dont think, just close. Then I took that piece of PVC with the angle cut and placed against the funnel where it would go through at and traced around the sides of it to give me a hole to cut. Cutting this with my jig saw was pretty easy with a fine tool metal blade.
Then I caulked around the base of the funnel, the seam in the funnel, and in between the bucket top and the piece of plywood. I loosened the screws between the bucket top and plywood so that I could get a good bit of caulk in here. I sat the funnel upright for the night to let it dry before tightening the screws. The weight of the funnel is pretty good at this point and keeps the joint there decently tight. Now when I tighten the screws in the morning the caulk will act as a gasket (learned that from sailboats although most of you reading probably already know that).