The next step toward finishing the Infinity Cycle was hiding the pits and valleys of my crap fiberglassing job with body filler. For those who have never used Bondo before, a word to the wise: It sets up really really fast, and a little goes a long way. My naive assumption was that I could spread it over the fin section all at once, and squeegee it off before it hardened. As it turns out, I barely had time to apply the Bondo at all before it solidified into a faux-stucco covering the lower half of the rocket. Sanding required an entire afternoon.
On another rocket related note, I just noticed that the Inverse Engineering guys posted my K450 static test to their website. Sweet.