what is a direct swap for a chevy 409?

[Mike V]

I have a 1964 Chevy C80 dumptruck with a 409 in it. I would like to change it over to a diesel and was wondering what if any would direct swap in its place. I don't need to do this but have and will be using it more and it only gets maybe a mile per gallon. Plus also it would be a project for me and my son to do this winter. Thanks for the help