383 vs 360 in an A 68 Cuda

It depends what you want. If you want a B engine for the cool factor, do it. More work, sure, but if that's what you want.
A 400 can easily be stroked out to around 500 cu in, and with aluminum heads, intake manifold and water pump, you can get the weight down to just a little bit more than a 360. Power steering was an option in '69, so if you really want it, it can be done.