I was very surprised to find out that there are NO callouts for the hardware that attaches the back spinner plate and propeller hub half to the Rotax 912iS. The assembly comes up in Section 37iS where the aft half of the propeller hub is attached to the back plate and engine before the top cowling half is intially fitted. The instructions say only "use the hardware provided" by does not indicate what hardware or in what order. The hardware bag contains six smaller bolts, six larger ones, some lock nuts, about a dozen or so Nordlock washers. You have to figure out how it all goes together, which is fine except that Van's provides such details on hundreds of other components and this seems like a pretty important one to relegate to the "you figure it out" state. (Update: Needed to use the Sensenich propeller instructions that should have come with the prop. They're online) It took some noodling and looking at pictures and a few emails to Van's support to finally figure out how they go. The Figure 1 illustration in Section 37 isn't helpful at all, nor is the propeller section in Section 47. There's no hardware callout for a two-blade prop, although, curiously, there is for the new three-blade prop. But I figured out, since the holes in the engine flange are too big for the bolts, that the bushings are inserted from the aft side of the engine gearbox flange, then the aft spinner plate, and then the aft half of the propeller hub. Six of the smaller bolts hold the whole sheabang in place and the drawing in Section 47 kind of suggests that one Nordlock washer (which is actually made up of two) goes under the bolt head and one goes under the net, although I have yet to get this confirmed. There's no safety wiring of this arrangement of bolt-washer-hub-spinner plate - bushing-engine flange - washer - nut configuration. After that was on, I started to add the tape to the forward edges of the to and bottom fuselage skins as a reference line. I drew a centerline on the top cowling and lined it up, and made the small angle that allows the top cowl to sit flush on the top of the spinner plate. Nice. Then I cut off a small part of the aft portion of the top cowl so it slipped between the skin and the spinner plate. Came out fine except I needed to add the top skin back on (I took it off to work on the ECU), so I put that back on. By then I'd already sanded the aft portion of the top cowl and it fit nice except in one small area where I took too much off. But I still have to make spacers for the spinner plate flange that should put it back 3/8" of an inch and close everything up nicely.