How long is your shaft?

[aitch]

I'm still investigating installing a one piece shaft in my 383 LWB coil spring.

Of course, I'm hoping to find a direct fit and not have to have a custom shaft built.
In my search, I found someone who had installed an aluminum 4" shaft from a late model GM truck. (Not sure what transmission)

Does anyone have a one piece shaft installed behind a 700R4? What is the length of the shaft? Did you find a direct fit?

Thanks.