Textured ceiling, new drywall on walls

Man, hard to get a title that means anything in so little space–here’s the deal: The house we are going to in MS has textured ceilings and they are in good shape and can stay up. We are putting up new drywall on the walls, so how do we get the tape smooth where walls meet ceilings? I told the “boss” to spray the popcorn ceilings with water and scrape the stuff off. He said that might work on some, but a couple ceilings have been textured with a knife and drywall compound (maybe even plaster that’s been textured) so it is hard. I suppose the only answer is to use topping compound to fill in and make it flat before running the new drywall?
I thought of somehow just doing a flat border, but that may be harder than doing the whole ceiling.
Oh, the ceilings are already low (7′-2″, IIRC), but I suppose we could still add 3/8″ drywall to them–being amatuers (or “semi-pro’s”) though, the lesss ceiling drywall we do, the better.
Replies
Easy-moulding, either crown or cove.
Harder-flat tape and/or cut to fit tite (wall drywall) and caulk.
A great place for Information, Comraderie, and a sucker punch.
Remodeling Contractor just outside the Glass City.
Quittin' Time
Thanks. I did suggest crown or cove molding, but he didn't seem too keen on the idea. Caulk is a good idea--assuming the guys can put up the wall drywall tight enough.