Can you get the vehicle in auto? Why must it be stick? Why must it be diesel?

Can you get the vehicle body and cobble together transmission and engine into it?

Kinda like destroked.com does. Take a Ford body and shove a Cummins engine in it because people like to go fast with less money spent.

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01 Ford Excursion Powerstroke
99 E300 Turbodiesel
91 Vette with 383 motor
05 Polaris Sportsman 800 EFI
06 Polaris Sportsman 500 EFI
03 SeaDoo GTX SC Red
03 SeaDoo GTX SC Yellow
04 Tailgator 21 ft Toy Hauler
11 Harley Davidson 883 SuperLow