I'm sorely tempted to do one before I retire, and likely retire the car. I'd freshen the 360 and sell it to free up some cash. My "vision" is a standard bore 5.7 with H-beam rods and a forged piston shooting for 10.5-11.0:1 compression. Basically stock heads, and a bigger cam that will still play nice with the stock rockers. I'd go the carb route, with something like an 850-950 Holley. I would obviously like to stick with my 904, and the 5.13's I'm currently running.
I currently run a motor plate and electric water pump. I see headers and ignition as big hurdles in a 69 Dart with a stock cross member. What else? As it stands, I don't see this being a tremendous deal, or am I dreaming in technicolor?