OK, using Kilz gray primer, I've primed the booster cluster and after a good drying period (I always wait at least 24 hrs), I'll finish with gloss OD or close to it.

I thought I'd be "smart" and fill in the balsa grain marks and front end of the transition. I used a product from Hobbico, called Hobbylite filler that "sands like balsa". In my opinion I waisted time and the transition is no better (maybe slightly worse) than before I started. Anyhow, I'll prime and see what it looks like. After painting, I'll attach booster fins, wrap end of booster and start on the sustainer section. Using my Dremel I've drilled 5 holes about 1/8th" into the root end in prep for Elmer's White glue. I plan to drill corresponding holes in the booster and attach . That should make a good connection. I wonder how the fillets will look, attaching white fins to an OD colored booster? I mean the Elmer's White will show won't it and the option to spray paint is not there.