Well put. Your best bet is hold onto those gears until you upgrade the engine. Without the right crank, it will be impossible to get the gears on.
Don't get too discouraged just yet, either. Trying to score cheap parts to hop up your car is great, but without a good game plan on what to get first to work with what you already have (and keep you from going in the poorhouse), it can get confusing. Stick to this thread; the guys in here have done about all there can be done to the CD3/LD3 and know what's what.
BTW, my great upgrade for '06 race season has begun. The last item I'll be getting is the CD3 pro from Tower (I should be able to get it down to about $230 if I work it right). In the meantime, to avoid canibalizing my LD3 (it's staying as a backup / 2nd car. Can't get rid of it after it won my class) I'll order all the parts it doesn't come with and have them ready (does the pro have the aluminum arm holders already? Can't remember)