With mine, I coated the centering rings with epoxy to strengthen them a little, replace the balsa fins with basswood, used a LOC/Precision 24mm motor tube with an Estes E length hook. For recovery, I wrapped a piece of kevlar line around the motor tube behinde the upper CR, then fed it through and out the top of the body tube about 4 inches, then tied a loop, and attached an elastic line to the nose cone (about four times the length of the original shock cord). I use a heat shield and the nylon chute from my AT Mustang when I fly it, and it flies on 24mm composite reloads, and loves it. I added some nose weight, but can't remember exactly how much off the top of my head. I think I just added nose weight in the same amount as the weight of an F12 reload, since that's the heaviest motor I would put it up on, since the F12 is heavier than the other reloads.
Loopy