Can anyone recommend a good reference source for installing a 6.6 liter Duramax (yes Chevy, client's request) into an 1948 F5? I tried several searches but have not found any for that vintage of truck.

 

I'm guessing you're treading uncharted territory. I don't recall anyone here tackling that combo. Give it a go and post a build thread. It would be an interesting project. I'm sure it'll be as straight forward as any engine swap ever is.