These guys are steering you correctly.
The car water pump housing is a direct bolt on. You will need to block the water inlets on the front of the heads. Pretty easy task. A flat plate and some gasket paper makes short work of that problem.
As stated, the pullies can be a bit tricky due to the fat damper.
Industrial and motorhome manifolds clear truck chassis without a problem.
Oz hit the important part. The engines have disturbingly low compression.
I had a 1973 413 that was a real odd ball. I stuffed it into my 1980 D100 but ran out of time to finish the build.