I did the impeller install on a JD 1032. For those who are unfamiliar with this machine, it has a very thick impeller, long, hard drilling. I made a paper mock up of the rubber, cutting & positioning it with pencil punched holes. I then put the paper mock up over the 4 rubber pieces clamped together and drilled all the holes at once in the rubber. I then used one of the rubber as a model to drill the holes in all four impeller blades. I put two 1/4" stainless steel truss head screws through one of the rubber through the impeller blade, reaching with my other hand through the auger rakes to put the 1/4" torque nut on the back of the impeller blade. I couldn't get it to thread. Turning the impeller blade so I could look at the back, I had inadvertently drilled the hole so close to the underside support rib that the side of the screw was kissing the rib and I couldn't put the nut on. There was no room for the nut as the rib was pushing the side of the nut off center from the screw. Fortunately the rib was short and did not extend all the way out and only one hole of each blade was affected but I still had to drill four new holes. I did this 2 months ago. Forgetting the previous rib problem, two days ago I started the impeller mod on a Ariens JD 826D cutting and drilling the holes in the four rubber pieces, drilling only one impeller blade this time then proceeding to install the one rubber only to have forgotten the previous rib lesson, again, too close to the rib. Fortunately only one rib was drilled, and the steel was thinner and easier to drill.