Green dot tranny conversion?

Hey Guys, I know it's been talked about before but I want to make sure converting a green dot tranny with a later valve body is worth it. I'm thinking about going this route and wonder just how much hp and abuse it could handle. The tranny shop here says they can do the valve body swap and rebuild the whole tranny with new converter for $700. I asked him how this conversion would make the green dot any different then a later C4 and he said the internal parts are the same in both except for the valve body. I'm not wanting to put to much hp into my 289 anyway since I want good mileage but figure no more then 240-260 max hp at the flywheel.
Has anyone out there done this swap? Let me know what you guys think, this'll be just a street car but I will lean on it off and on when the coast is clear.

You did ask this question before. Scroll down, pick page 4, and let us know if something has changed.

Nothing has changed since you last posted this question. Use a later model ('70 and up) C-4 in place of the earlier trans. You get a stronger input and better clutch drums. It is a straight bolt in, even if you have to swap bellhousings. For about the same money the trans shop is quoting you can buy a B+M or TCI built tranny that has the good parts. You can even buy and rebuild a trans yourself, not that hard. Why screw around with your early trans when you can easily upgrade? It's your money, do what you want...

sounds good to me 2ton....thanks