Trying to get the fincan/MM Tube to slide into the pre-sloted body tube took a lot of effort. Thankfully I was warned of this by my brother, and I was prepared.
First, as the instructions suggested I took off the 1/32" joint line that is at the middle of the fin can
Second, I sanded down the entire fincan (no, not the fins them selves), with 100 grit.
Saddly that was not enough, because when I dry fitted the assembly into the body tube, it still got stuck about 1/2" from where it needed to be. So out came the heavy artillary. I wraped 120 grit sand paper to a nylon ... something on a stick. I dont know that it really is, I always used it to cleah out RMS tubes. (see pic) . With this tool, I sanded the INSIDE of the body tube where the fincan was going.

This did help but I was still 1/4" short of the goal.
My next trick was to use my dremal and sand down/bevel the first 1/4" of the fincan. Finally, it fit.

Now it sits curing. Don't tighten the zip-tie too much, just make it snug, or else you will bow out the tube, the Fin-ders will not sit flat, and you will have that much more gap to fill.

While I waited I finished a few more steps on the AV-bay and top section. Specificly sanding the avbay so that it slipped in and out with out grabbing, and then marking, drilling, and reinforceing the rivit holes.

Greg Kurlinski (March 1, 2012)