If you want a Deere engine, you will want to use Dubuque engine: a 4045T (four cylinder turbocharged) or a 6068D. The D engine is not turbo'ed. A Deere engine with a T is turbo'ed and and A is turbo'ed and aftercooled. Dubuque engines are very popular in a wide variety of industrial and smaller ag equipment.
Deere's other engine series are called Waterloo engines and are MUCH heavier than the Dubuques.
You can get a SAE #2 flywheel housing which would allow you to bolt up anything from an Allison automatic to a Roadranger truck transmission.
A diesel engine typically is governed out at 2300 RPM, so the vehicle needs to be geared accordingly.
