I have a couple 6" sticky back 220 grit sanding discs stuck to a piece of Melamine coated particle board for sanding. Take the body tube and twist it as you criss cross sand the body tube until it gets smooth. But DO NOT sand through the coating. (If you do sand through, sand after the first coat of glue to get rid of the knobs. Give that area(s) a thin coat of glue to seal it, then recoat the entire tube) After sanding, I mark for fins and the launch lug. I use a different color for the launch lug so a mistake doesn't happen and you put a fin in the wrong place. (yeup, I've done that) I have several sets of Estes Accessories so I use the fin marking guides to hold the BT while I coat it with TiteBond III. (I've tried all the TiteBond's, and the III sand's the easiest without gumming and clogging.) I gave this tube one good heavy even coat and that was enough to sand smooth. Using the same criss cross while you twist sanding you get a nice round and even finish. While the BT is drying up, I started on the Engine Mount. I followed the instructions and didn't test fit it. I thought since the Alpha has been around a long time, the instructions would be correct. However, to pull the engine hook back far enough to get the engine in and out, you stretch the BT. My choice was to slot the BT and glue the inside of the TB around the cut out. Since the Engine Mount had already been glued in place, I didn't have much choice. ALWAYS test fit! Some sanding was necessary to make things fit proper. I added fillets on the sleeve and engine block before gluing the engine mount in place as well. When gluing the engine mount assembly in place, I applied an ample amount inside the BT and twisted it several times to make sure there was good coverage all around the centering sleeve. When it began to grab, I set the engine hook to line up with the launch lug line. The kit DID NOT include a engine block. I chose to add one. It is too easy for the engine hook to slide up through the cut you make in the engine mount tube without one. (This has happened to me before, so I always add an engine block/thrust ring) I use the tube marking gauge to make sure the engine hook goes in straight, and mark for the wide centering ring. (I'll be doing a scratch build using 2 centering rings with kevlar to correct the error with the way the engine hook stretches the BT, and to eliminate the folding rubber band shock cord mount.